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/debug_locks.h> 14 #include <linux/mm_types.h> 15 16 struct mempolicy; 17 struct anon_vma; 18 struct file_ra_state; 19 struct user_struct; 20 struct writeback_control; 21 struct rlimit; 22 23 #ifndef CONFIG_DISCONTIGMEM /* Don't use mapnrs, do it properly */ 24 extern unsigned long max_mapnr; 25 #endif 26 27 extern unsigned long num_physpages; 28 extern void * high_memory; 29 extern int page_cluster; 30 31 #ifdef CONFIG_SYSCTL 32 extern int sysctl_legacy_va_layout; 33 #else 34 #define sysctl_legacy_va_layout 0 35 #endif 36 37 #include <asm/page.h> 38 #include <asm/pgtable.h> 39 #include <asm/processor.h> 40 41 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n)) 42 43 /* to align the pointer to the (next) page boundary */ 44 #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE) 45 46 /* 47 * Linux kernel virtual memory manager primitives. 48 * The idea being to have a "virtual" mm in the same way 49 * we have a virtual fs - giving a cleaner interface to the 50 * mm details, and allowing different kinds of memory mappings 51 * (from shared memory to executable loading to arbitrary 52 * mmap() functions). 53 */ 54 55 extern struct kmem_cache *vm_area_cachep; 56 57 #ifndef CONFIG_MMU 58 extern struct rb_root nommu_region_tree; 59 extern struct rw_semaphore nommu_region_sem; 60 61 extern unsigned int kobjsize(const void *objp); 62 #endif 63 64 /* 65 * vm_flags in vm_area_struct, see mm_types.h. 66 */ 67 #define VM_READ 0x00000001 /* currently active flags */ 68 #define VM_WRITE 0x00000002 69 #define VM_EXEC 0x00000004 70 #define VM_SHARED 0x00000008 71 72 /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */ 73 #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */ 74 #define VM_MAYWRITE 0x00000020 75 #define VM_MAYEXEC 0x00000040 76 #define VM_MAYSHARE 0x00000080 77 78 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */ 79 #define VM_GROWSUP 0x00000200 80 #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */ 81 #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */ 82 83 #define VM_EXECUTABLE 0x00001000 84 #define VM_LOCKED 0x00002000 85 #define VM_IO 0x00004000 /* Memory mapped I/O or similar */ 86 87 /* Used by sys_madvise() */ 88 #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */ 89 #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */ 90 91 #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ 92 #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ 93 #define VM_RESERVED 0x00080000 /* Count as reserved_vm like IO */ 94 #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */ 95 #define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */ 96 #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ 97 #define VM_NONLINEAR 0x00800000 /* Is non-linear (remap_file_pages) */ 98 #define VM_MAPPED_COPY 0x01000000 /* T if mapped copy of data (nommu mmap) */ 99 #define VM_INSERTPAGE 0x02000000 /* The vma has had "vm_insert_page()" done on it */ 100 #define VM_ALWAYSDUMP 0x04000000 /* Always include in core dumps */ 101 102 #define VM_CAN_NONLINEAR 0x08000000 /* Has ->fault & does nonlinear pages */ 103 #define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */ 104 #define VM_SAO 0x20000000 /* Strong Access Ordering (powerpc) */ 105 #define VM_PFN_AT_MMAP 0x40000000 /* PFNMAP vma that is fully mapped at mmap time */ 106 107 #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */ 108 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS 109 #endif 110 111 #ifdef CONFIG_STACK_GROWSUP 112 #define VM_STACK_FLAGS (VM_GROWSUP | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) 113 #else 114 #define VM_STACK_FLAGS (VM_GROWSDOWN | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) 115 #endif 116 117 #define VM_READHINTMASK (VM_SEQ_READ | VM_RAND_READ) 118 #define VM_ClearReadHint(v) (v)->vm_flags &= ~VM_READHINTMASK 119 #define VM_NormalReadHint(v) (!((v)->vm_flags & VM_READHINTMASK)) 120 #define VM_SequentialReadHint(v) ((v)->vm_flags & VM_SEQ_READ) 121 #define VM_RandomReadHint(v) ((v)->vm_flags & VM_RAND_READ) 122 123 /* 124 * special vmas that are non-mergable, non-mlock()able 125 */ 126 #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_RESERVED | VM_PFNMAP) 127 128 /* 129 * mapping from the currently active vm_flags protection bits (the 130 * low four bits) to a page protection mask.. 131 */ 132 extern pgprot_t protection_map[16]; 133 134 #define FAULT_FLAG_WRITE 0x01 /* Fault was a write access */ 135 #define FAULT_FLAG_NONLINEAR 0x02 /* Fault was via a nonlinear mapping */ 136 #define FAULT_FLAG_MKWRITE 0x04 /* Fault was mkwrite of existing pte */ 137 138 /* 139 * This interface is used by x86 PAT code to identify a pfn mapping that is 140 * linear over entire vma. This is to optimize PAT code that deals with 141 * marking the physical region with a particular prot. This is not for generic 142 * mm use. Note also that this check will not work if the pfn mapping is 143 * linear for a vma starting at physical address 0. In which case PAT code 144 * falls back to slow path of reserving physical range page by page. 145 */ 146 static inline int is_linear_pfn_mapping(struct vm_area_struct *vma) 147 { 148 return (vma->vm_flags & VM_PFN_AT_MMAP); 149 } 150 151 static inline int is_pfn_mapping(struct vm_area_struct *vma) 152 { 153 return (vma->vm_flags & VM_PFNMAP); 154 } 155 156 /* 157 * vm_fault is filled by the the pagefault handler and passed to the vma's 158 * ->fault function. The vma's ->fault is responsible for returning a bitmask 159 * of VM_FAULT_xxx flags that give details about how the fault was handled. 160 * 161 * pgoff should be used in favour of virtual_address, if possible. If pgoff 162 * is used, one may set VM_CAN_NONLINEAR in the vma->vm_flags to get nonlinear 163 * mapping support. 164 */ 165 struct vm_fault { 166 unsigned int flags; /* FAULT_FLAG_xxx flags */ 167 pgoff_t pgoff; /* Logical page offset based on vma */ 168 void __user *virtual_address; /* Faulting virtual address */ 169 170 struct page *page; /* ->fault handlers should return a 171 * page here, unless VM_FAULT_NOPAGE 172 * is set (which is also implied by 173 * VM_FAULT_ERROR). 174 */ 175 }; 176 177 /* 178 * These are the virtual MM functions - opening of an area, closing and 179 * unmapping it (needed to keep files on disk up-to-date etc), pointer 180 * to the functions called when a no-page or a wp-page exception occurs. 181 */ 182 struct vm_operations_struct { 183 void (*open)(struct vm_area_struct * area); 184 void (*close)(struct vm_area_struct * area); 185 int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf); 186 187 /* notification that a previously read-only page is about to become 188 * writable, if an error is returned it will cause a SIGBUS */ 189 int (*page_mkwrite)(struct vm_area_struct *vma, struct vm_fault *vmf); 190 191 /* called by access_process_vm when get_user_pages() fails, typically 192 * for use by special VMAs that can switch between memory and hardware 193 */ 194 int (*access)(struct vm_area_struct *vma, unsigned long addr, 195 void *buf, int len, int write); 196 #ifdef CONFIG_NUMA 197 /* 198 * set_policy() op must add a reference to any non-NULL @new mempolicy 199 * to hold the policy upon return. Caller should pass NULL @new to 200 * remove a policy and fall back to surrounding context--i.e. do not 201 * install a MPOL_DEFAULT policy, nor the task or system default 202 * mempolicy. 203 */ 204 int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); 205 206 /* 207 * get_policy() op must add reference [mpol_get()] to any policy at 208 * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure 209 * in mm/mempolicy.c will do this automatically. 210 * get_policy() must NOT add a ref if the policy at (vma,addr) is not 211 * marked as MPOL_SHARED. vma policies are protected by the mmap_sem. 212 * If no [shared/vma] mempolicy exists at the addr, get_policy() op 213 * must return NULL--i.e., do not "fallback" to task or system default 214 * policy. 215 */ 216 struct mempolicy *(*get_policy)(struct vm_area_struct *vma, 217 unsigned long addr); 218 int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from, 219 const nodemask_t *to, unsigned long flags); 220 #endif 221 }; 222 223 struct mmu_gather; 224 struct inode; 225 226 #define page_private(page) ((page)->private) 227 #define set_page_private(page, v) ((page)->private = (v)) 228 229 /* 230 * FIXME: take this include out, include page-flags.h in 231 * files which need it (119 of them) 232 */ 233 #include <linux/page-flags.h> 234 235 /* 236 * Methods to modify the page usage count. 237 * 238 * What counts for a page usage: 239 * - cache mapping (page->mapping) 240 * - private data (page->private) 241 * - page mapped in a task's page tables, each mapping 242 * is counted separately 243 * 244 * Also, many kernel routines increase the page count before a critical 245 * routine so they can be sure the page doesn't go away from under them. 246 */ 247 248 /* 249 * Drop a ref, return true if the refcount fell to zero (the page has no users) 250 */ 251 static inline int put_page_testzero(struct page *page) 252 { 253 VM_BUG_ON(atomic_read(&page->_count) == 0); 254 return atomic_dec_and_test(&page->_count); 255 } 256 257 /* 258 * Try to grab a ref unless the page has a refcount of zero, return false if 259 * that is the case. 260 */ 261 static inline int get_page_unless_zero(struct page *page) 262 { 263 return atomic_inc_not_zero(&page->_count); 264 } 265 266 /* Support for virtually mapped pages */ 267 struct page *vmalloc_to_page(const void *addr); 268 unsigned long vmalloc_to_pfn(const void *addr); 269 270 /* 271 * Determine if an address is within the vmalloc range 272 * 273 * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there 274 * is no special casing required. 275 */ 276 static inline int is_vmalloc_addr(const void *x) 277 { 278 #ifdef CONFIG_MMU 279 unsigned long addr = (unsigned long)x; 280 281 return addr >= VMALLOC_START && addr < VMALLOC_END; 282 #else 283 return 0; 284 #endif 285 } 286 287 static inline struct page *compound_head(struct page *page) 288 { 289 if (unlikely(PageTail(page))) 290 return page->first_page; 291 return page; 292 } 293 294 static inline int page_count(struct page *page) 295 { 296 return atomic_read(&compound_head(page)->_count); 297 } 298 299 static inline void get_page(struct page *page) 300 { 301 page = compound_head(page); 302 VM_BUG_ON(atomic_read(&page->_count) == 0); 303 atomic_inc(&page->_count); 304 } 305 306 static inline struct page *virt_to_head_page(const void *x) 307 { 308 struct page *page = virt_to_page(x); 309 return compound_head(page); 310 } 311 312 /* 313 * Setup the page count before being freed into the page allocator for 314 * the first time (boot or memory hotplug) 315 */ 316 static inline void init_page_count(struct page *page) 317 { 318 atomic_set(&page->_count, 1); 319 } 320 321 void put_page(struct page *page); 322 void put_pages_list(struct list_head *pages); 323 324 void split_page(struct page *page, unsigned int order); 325 326 /* 327 * Compound pages have a destructor function. Provide a 328 * prototype for that function and accessor functions. 329 * These are _only_ valid on the head of a PG_compound page. 330 */ 331 typedef void compound_page_dtor(struct page *); 332 333 static inline void set_compound_page_dtor(struct page *page, 334 compound_page_dtor *dtor) 335 { 336 page[1].lru.next = (void *)dtor; 337 } 338 339 static inline compound_page_dtor *get_compound_page_dtor(struct page *page) 340 { 341 return (compound_page_dtor *)page[1].lru.next; 342 } 343 344 static inline int compound_order(struct page *page) 345 { 346 if (!PageHead(page)) 347 return 0; 348 return (unsigned long)page[1].lru.prev; 349 } 350 351 static inline void set_compound_order(struct page *page, unsigned long order) 352 { 353 page[1].lru.prev = (void *)order; 354 } 355 356 /* 357 * Multiple processes may "see" the same page. E.g. for untouched 358 * mappings of /dev/null, all processes see the same page full of 359 * zeroes, and text pages of executables and shared libraries have 360 * only one copy in memory, at most, normally. 361 * 362 * For the non-reserved pages, page_count(page) denotes a reference count. 363 * page_count() == 0 means the page is free. page->lru is then used for 364 * freelist management in the buddy allocator. 365 * page_count() > 0 means the page has been allocated. 366 * 367 * Pages are allocated by the slab allocator in order to provide memory 368 * to kmalloc and kmem_cache_alloc. In this case, the management of the 369 * page, and the fields in 'struct page' are the responsibility of mm/slab.c 370 * unless a particular usage is carefully commented. (the responsibility of 371 * freeing the kmalloc memory is the caller's, of course). 372 * 373 * A page may be used by anyone else who does a __get_free_page(). 374 * In this case, page_count still tracks the references, and should only 375 * be used through the normal accessor functions. The top bits of page->flags 376 * and page->virtual store page management information, but all other fields 377 * are unused and could be used privately, carefully. The management of this 378 * page is the responsibility of the one who allocated it, and those who have 379 * subsequently been given references to it. 380 * 381 * The other pages (we may call them "pagecache pages") are completely 382 * managed by the Linux memory manager: I/O, buffers, swapping etc. 383 * The following discussion applies only to them. 384 * 385 * A pagecache page contains an opaque `private' member, which belongs to the 386 * page's address_space. Usually, this is the address of a circular list of 387 * the page's disk buffers. PG_private must be set to tell the VM to call 388 * into the filesystem to release these pages. 389 * 390 * A page may belong to an inode's memory mapping. In this case, page->mapping 391 * is the pointer to the inode, and page->index is the file offset of the page, 392 * in units of PAGE_CACHE_SIZE. 393 * 394 * If pagecache pages are not associated with an inode, they are said to be 395 * anonymous pages. These may become associated with the swapcache, and in that 396 * case PG_swapcache is set, and page->private is an offset into the swapcache. 397 * 398 * In either case (swapcache or inode backed), the pagecache itself holds one 399 * reference to the page. Setting PG_private should also increment the 400 * refcount. The each user mapping also has a reference to the page. 401 * 402 * The pagecache pages are stored in a per-mapping radix tree, which is 403 * rooted at mapping->page_tree, and indexed by offset. 404 * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space 405 * lists, we instead now tag pages as dirty/writeback in the radix tree. 406 * 407 * All pagecache pages may be subject to I/O: 408 * - inode pages may need to be read from disk, 409 * - inode pages which have been modified and are MAP_SHARED may need 410 * to be written back to the inode on disk, 411 * - anonymous pages (including MAP_PRIVATE file mappings) which have been 412 * modified may need to be swapped out to swap space and (later) to be read 413 * back into memory. 414 */ 415 416 /* 417 * The zone field is never updated after free_area_init_core() 418 * sets it, so none of the operations on it need to be atomic. 419 */ 420 421 422 /* 423 * page->flags layout: 424 * 425 * There are three possibilities for how page->flags get 426 * laid out. The first is for the normal case, without 427 * sparsemem. The second is for sparsemem when there is 428 * plenty of space for node and section. The last is when 429 * we have run out of space and have to fall back to an 430 * alternate (slower) way of determining the node. 431 * 432 * No sparsemem or sparsemem vmemmap: | NODE | ZONE | ... | FLAGS | 433 * classic sparse with space for node:| SECTION | NODE | ZONE | ... | FLAGS | 434 * classic sparse no space for node: | SECTION | ZONE | ... | FLAGS | 435 */ 436 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) 437 #define SECTIONS_WIDTH SECTIONS_SHIFT 438 #else 439 #define SECTIONS_WIDTH 0 440 #endif 441 442 #define ZONES_WIDTH ZONES_SHIFT 443 444 #if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT <= BITS_PER_LONG - NR_PAGEFLAGS 445 #define NODES_WIDTH NODES_SHIFT 446 #else 447 #ifdef CONFIG_SPARSEMEM_VMEMMAP 448 #error "Vmemmap: No space for nodes field in page flags" 449 #endif 450 #define NODES_WIDTH 0 451 #endif 452 453 /* Page flags: | [SECTION] | [NODE] | ZONE | ... | FLAGS | */ 454 #define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH) 455 #define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH) 456 #define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH) 457 458 /* 459 * We are going to use the flags for the page to node mapping if its in 460 * there. This includes the case where there is no node, so it is implicit. 461 */ 462 #if !(NODES_WIDTH > 0 || NODES_SHIFT == 0) 463 #define NODE_NOT_IN_PAGE_FLAGS 464 #endif 465 466 #ifndef PFN_SECTION_SHIFT 467 #define PFN_SECTION_SHIFT 0 468 #endif 469 470 /* 471 * Define the bit shifts to access each section. For non-existant 472 * sections we define the shift as 0; that plus a 0 mask ensures 473 * the compiler will optimise away reference to them. 474 */ 475 #define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0)) 476 #define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0)) 477 #define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0)) 478 479 /* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allcator */ 480 #ifdef NODE_NOT_IN_PAGEFLAGS 481 #define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT) 482 #define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF)? \ 483 SECTIONS_PGOFF : ZONES_PGOFF) 484 #else 485 #define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT) 486 #define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF)? \ 487 NODES_PGOFF : ZONES_PGOFF) 488 #endif 489 490 #define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0)) 491 492 #if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS 493 #error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS 494 #endif 495 496 #define ZONES_MASK ((1UL << ZONES_WIDTH) - 1) 497 #define NODES_MASK ((1UL << NODES_WIDTH) - 1) 498 #define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1) 499 #define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1) 500 501 static inline enum zone_type page_zonenum(struct page *page) 502 { 503 return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK; 504 } 505 506 /* 507 * The identification function is only used by the buddy allocator for 508 * determining if two pages could be buddies. We are not really 509 * identifying a zone since we could be using a the section number 510 * id if we have not node id available in page flags. 511 * We guarantee only that it will return the same value for two 512 * combinable pages in a zone. 513 */ 514 static inline int page_zone_id(struct page *page) 515 { 516 return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK; 517 } 518 519 static inline int zone_to_nid(struct zone *zone) 520 { 521 #ifdef CONFIG_NUMA 522 return zone->node; 523 #else 524 return 0; 525 #endif 526 } 527 528 #ifdef NODE_NOT_IN_PAGE_FLAGS 529 extern int page_to_nid(struct page *page); 530 #else 531 static inline int page_to_nid(struct page *page) 532 { 533 return (page->flags >> NODES_PGSHIFT) & NODES_MASK; 534 } 535 #endif 536 537 static inline struct zone *page_zone(struct page *page) 538 { 539 return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)]; 540 } 541 542 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) 543 static inline unsigned long page_to_section(struct page *page) 544 { 545 return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK; 546 } 547 #endif 548 549 static inline void set_page_zone(struct page *page, enum zone_type zone) 550 { 551 page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT); 552 page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT; 553 } 554 555 static inline void set_page_node(struct page *page, unsigned long node) 556 { 557 page->flags &= ~(NODES_MASK << NODES_PGSHIFT); 558 page->flags |= (node & NODES_MASK) << NODES_PGSHIFT; 559 } 560 561 static inline void set_page_section(struct page *page, unsigned long section) 562 { 563 page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT); 564 page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT; 565 } 566 567 static inline void set_page_links(struct page *page, enum zone_type zone, 568 unsigned long node, unsigned long pfn) 569 { 570 set_page_zone(page, zone); 571 set_page_node(page, node); 572 set_page_section(page, pfn_to_section_nr(pfn)); 573 } 574 575 /* 576 * Some inline functions in vmstat.h depend on page_zone() 577 */ 578 #include <linux/vmstat.h> 579 580 static __always_inline void *lowmem_page_address(struct page *page) 581 { 582 return __va(page_to_pfn(page) << PAGE_SHIFT); 583 } 584 585 #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) 586 #define HASHED_PAGE_VIRTUAL 587 #endif 588 589 #if defined(WANT_PAGE_VIRTUAL) 590 #define page_address(page) ((page)->virtual) 591 #define set_page_address(page, address) \ 592 do { \ 593 (page)->virtual = (address); \ 594 } while(0) 595 #define page_address_init() do { } while(0) 596 #endif 597 598 #if defined(HASHED_PAGE_VIRTUAL) 599 void *page_address(struct page *page); 600 void set_page_address(struct page *page, void *virtual); 601 void page_address_init(void); 602 #endif 603 604 #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL) 605 #define page_address(page) lowmem_page_address(page) 606 #define set_page_address(page, address) do { } while(0) 607 #define page_address_init() do { } while(0) 608 #endif 609 610 /* 611 * On an anonymous page mapped into a user virtual memory area, 612 * page->mapping points to its anon_vma, not to a struct address_space; 613 * with the PAGE_MAPPING_ANON bit set to distinguish it. 614 * 615 * Please note that, confusingly, "page_mapping" refers to the inode 616 * address_space which maps the page from disk; whereas "page_mapped" 617 * refers to user virtual address space into which the page is mapped. 618 */ 619 #define PAGE_MAPPING_ANON 1 620 621 extern struct address_space swapper_space; 622 static inline struct address_space *page_mapping(struct page *page) 623 { 624 struct address_space *mapping = page->mapping; 625 626 VM_BUG_ON(PageSlab(page)); 627 #ifdef CONFIG_SWAP 628 if (unlikely(PageSwapCache(page))) 629 mapping = &swapper_space; 630 else 631 #endif 632 if (unlikely((unsigned long)mapping & PAGE_MAPPING_ANON)) 633 mapping = NULL; 634 return mapping; 635 } 636 637 static inline int PageAnon(struct page *page) 638 { 639 return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0; 640 } 641 642 /* 643 * Return the pagecache index of the passed page. Regular pagecache pages 644 * use ->index whereas swapcache pages use ->private 645 */ 646 static inline pgoff_t page_index(struct page *page) 647 { 648 if (unlikely(PageSwapCache(page))) 649 return page_private(page); 650 return page->index; 651 } 652 653 /* 654 * The atomic page->_mapcount, like _count, starts from -1: 655 * so that transitions both from it and to it can be tracked, 656 * using atomic_inc_and_test and atomic_add_negative(-1). 657 */ 658 static inline void reset_page_mapcount(struct page *page) 659 { 660 atomic_set(&(page)->_mapcount, -1); 661 } 662 663 static inline int page_mapcount(struct page *page) 664 { 665 return atomic_read(&(page)->_mapcount) + 1; 666 } 667 668 /* 669 * Return true if this page is mapped into pagetables. 670 */ 671 static inline int page_mapped(struct page *page) 672 { 673 return atomic_read(&(page)->_mapcount) >= 0; 674 } 675 676 /* 677 * Different kinds of faults, as returned by handle_mm_fault(). 678 * Used to decide whether a process gets delivered SIGBUS or 679 * just gets major/minor fault counters bumped up. 680 */ 681 682 #define VM_FAULT_MINOR 0 /* For backwards compat. Remove me quickly. */ 683 684 #define VM_FAULT_OOM 0x0001 685 #define VM_FAULT_SIGBUS 0x0002 686 #define VM_FAULT_MAJOR 0x0004 687 #define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */ 688 689 #define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */ 690 #define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */ 691 692 #define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS) 693 694 /* 695 * Can be called by the pagefault handler when it gets a VM_FAULT_OOM. 696 */ 697 extern void pagefault_out_of_memory(void); 698 699 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) 700 701 extern void show_free_areas(void); 702 703 #ifdef CONFIG_SHMEM 704 extern int shmem_lock(struct file *file, int lock, struct user_struct *user); 705 #else 706 static inline int shmem_lock(struct file *file, int lock, 707 struct user_struct *user) 708 { 709 return 0; 710 } 711 #endif 712 struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags); 713 714 int shmem_zero_setup(struct vm_area_struct *); 715 716 #ifndef CONFIG_MMU 717 extern unsigned long shmem_get_unmapped_area(struct file *file, 718 unsigned long addr, 719 unsigned long len, 720 unsigned long pgoff, 721 unsigned long flags); 722 #endif 723 724 extern int can_do_mlock(void); 725 extern int user_shm_lock(size_t, struct user_struct *); 726 extern void user_shm_unlock(size_t, struct user_struct *); 727 728 /* 729 * Parameter block passed down to zap_pte_range in exceptional cases. 730 */ 731 struct zap_details { 732 struct vm_area_struct *nonlinear_vma; /* Check page->index if set */ 733 struct address_space *check_mapping; /* Check page->mapping if set */ 734 pgoff_t first_index; /* Lowest page->index to unmap */ 735 pgoff_t last_index; /* Highest page->index to unmap */ 736 spinlock_t *i_mmap_lock; /* For unmap_mapping_range: */ 737 unsigned long truncate_count; /* Compare vm_truncate_count */ 738 }; 739 740 struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, 741 pte_t pte); 742 743 int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address, 744 unsigned long size); 745 unsigned long zap_page_range(struct vm_area_struct *vma, unsigned long address, 746 unsigned long size, struct zap_details *); 747 unsigned long unmap_vmas(struct mmu_gather **tlb, 748 struct vm_area_struct *start_vma, unsigned long start_addr, 749 unsigned long end_addr, unsigned long *nr_accounted, 750 struct zap_details *); 751 752 /** 753 * mm_walk - callbacks for walk_page_range 754 * @pgd_entry: if set, called for each non-empty PGD (top-level) entry 755 * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry 756 * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry 757 * @pte_entry: if set, called for each non-empty PTE (4th-level) entry 758 * @pte_hole: if set, called for each hole at all levels 759 * 760 * (see walk_page_range for more details) 761 */ 762 struct mm_walk { 763 int (*pgd_entry)(pgd_t *, unsigned long, unsigned long, struct mm_walk *); 764 int (*pud_entry)(pud_t *, unsigned long, unsigned long, struct mm_walk *); 765 int (*pmd_entry)(pmd_t *, unsigned long, unsigned long, struct mm_walk *); 766 int (*pte_entry)(pte_t *, unsigned long, unsigned long, struct mm_walk *); 767 int (*pte_hole)(unsigned long, unsigned long, struct mm_walk *); 768 struct mm_struct *mm; 769 void *private; 770 }; 771 772 int walk_page_range(unsigned long addr, unsigned long end, 773 struct mm_walk *walk); 774 void free_pgd_range(struct mmu_gather *tlb, unsigned long addr, 775 unsigned long end, unsigned long floor, unsigned long ceiling); 776 int copy_page_range(struct mm_struct *dst, struct mm_struct *src, 777 struct vm_area_struct *vma); 778 void unmap_mapping_range(struct address_space *mapping, 779 loff_t const holebegin, loff_t const holelen, int even_cows); 780 int follow_pfn(struct vm_area_struct *vma, unsigned long address, 781 unsigned long *pfn); 782 int follow_phys(struct vm_area_struct *vma, unsigned long address, 783 unsigned int flags, unsigned long *prot, resource_size_t *phys); 784 int generic_access_phys(struct vm_area_struct *vma, unsigned long addr, 785 void *buf, int len, int write); 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, unsigned int flags); 799 #else 800 static inline int handle_mm_fault(struct mm_struct *mm, 801 struct vm_area_struct *vma, unsigned long address, 802 unsigned int flags) 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, 814 unsigned long start, int nr_pages, int write, int force, 815 struct page **pages, struct vm_area_struct **vmas); 816 int get_user_pages_fast(unsigned long start, int nr_pages, int write, 817 struct page **pages); 818 819 extern int try_to_release_page(struct page * page, gfp_t gfp_mask); 820 extern void do_invalidatepage(struct page *page, unsigned long offset); 821 822 int __set_page_dirty_nobuffers(struct page *page); 823 int __set_page_dirty_no_writeback(struct page *page); 824 int redirty_page_for_writepage(struct writeback_control *wbc, 825 struct page *page); 826 void account_page_dirtied(struct page *page, struct address_space *mapping); 827 int set_page_dirty(struct page *page); 828 int set_page_dirty_lock(struct page *page); 829 int clear_page_dirty_for_io(struct page *page); 830 831 extern unsigned long move_page_tables(struct vm_area_struct *vma, 832 unsigned long old_addr, struct vm_area_struct *new_vma, 833 unsigned long new_addr, unsigned long len); 834 extern unsigned long do_mremap(unsigned long addr, 835 unsigned long old_len, unsigned long new_len, 836 unsigned long flags, unsigned long new_addr); 837 extern int mprotect_fixup(struct vm_area_struct *vma, 838 struct vm_area_struct **pprev, unsigned long start, 839 unsigned long end, unsigned long newflags); 840 841 /* 842 * doesn't attempt to fault and will return short. 843 */ 844 int __get_user_pages_fast(unsigned long start, int nr_pages, int write, 845 struct page **pages); 846 847 /* 848 * A callback you can register to apply pressure to ageable caches. 849 * 850 * 'shrink' is passed a count 'nr_to_scan' and a 'gfpmask'. It should 851 * look through the least-recently-used 'nr_to_scan' entries and 852 * attempt to free them up. It should return the number of objects 853 * which remain in the cache. If it returns -1, it means it cannot do 854 * any scanning at this time (eg. there is a risk of deadlock). 855 * 856 * The 'gfpmask' refers to the allocation we are currently trying to 857 * fulfil. 858 * 859 * Note that 'shrink' will be passed nr_to_scan == 0 when the VM is 860 * querying the cache size, so a fastpath for that case is appropriate. 861 */ 862 struct shrinker { 863 int (*shrink)(int nr_to_scan, gfp_t gfp_mask); 864 int seeks; /* seeks to recreate an obj */ 865 866 /* These are for internal use */ 867 struct list_head list; 868 long nr; /* objs pending delete */ 869 }; 870 #define DEFAULT_SEEKS 2 /* A good number if you don't know better. */ 871 extern void register_shrinker(struct shrinker *); 872 extern void unregister_shrinker(struct shrinker *); 873 874 int vma_wants_writenotify(struct vm_area_struct *vma); 875 876 extern pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr, spinlock_t **ptl); 877 878 #ifdef __PAGETABLE_PUD_FOLDED 879 static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, 880 unsigned long address) 881 { 882 return 0; 883 } 884 #else 885 int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address); 886 #endif 887 888 #ifdef __PAGETABLE_PMD_FOLDED 889 static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud, 890 unsigned long address) 891 { 892 return 0; 893 } 894 #else 895 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); 896 #endif 897 898 int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address); 899 int __pte_alloc_kernel(pmd_t *pmd, unsigned long address); 900 901 /* 902 * The following ifdef needed to get the 4level-fixup.h header to work. 903 * Remove it when 4level-fixup.h has been removed. 904 */ 905 #if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK) 906 static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address) 907 { 908 return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))? 909 NULL: pud_offset(pgd, address); 910 } 911 912 static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) 913 { 914 return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))? 915 NULL: pmd_offset(pud, address); 916 } 917 #endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */ 918 919 #if USE_SPLIT_PTLOCKS 920 /* 921 * We tuck a spinlock to guard each pagetable page into its struct page, 922 * at page->private, with BUILD_BUG_ON to make sure that this will not 923 * overflow into the next struct page (as it might with DEBUG_SPINLOCK). 924 * When freeing, reset page->mapping so free_pages_check won't complain. 925 */ 926 #define __pte_lockptr(page) &((page)->ptl) 927 #define pte_lock_init(_page) do { \ 928 spin_lock_init(__pte_lockptr(_page)); \ 929 } while (0) 930 #define pte_lock_deinit(page) ((page)->mapping = NULL) 931 #define pte_lockptr(mm, pmd) ({(void)(mm); __pte_lockptr(pmd_page(*(pmd)));}) 932 #else /* !USE_SPLIT_PTLOCKS */ 933 /* 934 * We use mm->page_table_lock to guard all pagetable pages of the mm. 935 */ 936 #define pte_lock_init(page) do {} while (0) 937 #define pte_lock_deinit(page) do {} while (0) 938 #define pte_lockptr(mm, pmd) ({(void)(pmd); &(mm)->page_table_lock;}) 939 #endif /* USE_SPLIT_PTLOCKS */ 940 941 static inline void pgtable_page_ctor(struct page *page) 942 { 943 pte_lock_init(page); 944 inc_zone_page_state(page, NR_PAGETABLE); 945 } 946 947 static inline void pgtable_page_dtor(struct page *page) 948 { 949 pte_lock_deinit(page); 950 dec_zone_page_state(page, NR_PAGETABLE); 951 } 952 953 #define pte_offset_map_lock(mm, pmd, address, ptlp) \ 954 ({ \ 955 spinlock_t *__ptl = pte_lockptr(mm, pmd); \ 956 pte_t *__pte = pte_offset_map(pmd, address); \ 957 *(ptlp) = __ptl; \ 958 spin_lock(__ptl); \ 959 __pte; \ 960 }) 961 962 #define pte_unmap_unlock(pte, ptl) do { \ 963 spin_unlock(ptl); \ 964 pte_unmap(pte); \ 965 } while (0) 966 967 #define pte_alloc_map(mm, pmd, address) \ 968 ((unlikely(!pmd_present(*(pmd))) && __pte_alloc(mm, pmd, address))? \ 969 NULL: pte_offset_map(pmd, address)) 970 971 #define pte_alloc_map_lock(mm, pmd, address, ptlp) \ 972 ((unlikely(!pmd_present(*(pmd))) && __pte_alloc(mm, pmd, address))? \ 973 NULL: pte_offset_map_lock(mm, pmd, address, ptlp)) 974 975 #define pte_alloc_kernel(pmd, address) \ 976 ((unlikely(!pmd_present(*(pmd))) && __pte_alloc_kernel(pmd, address))? \ 977 NULL: pte_offset_kernel(pmd, address)) 978 979 extern void free_area_init(unsigned long * zones_size); 980 extern void free_area_init_node(int nid, unsigned long * zones_size, 981 unsigned long zone_start_pfn, unsigned long *zholes_size); 982 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP 983 /* 984 * With CONFIG_ARCH_POPULATES_NODE_MAP set, an architecture may initialise its 985 * zones, allocate the backing mem_map and account for memory holes in a more 986 * architecture independent manner. This is a substitute for creating the 987 * zone_sizes[] and zholes_size[] arrays and passing them to 988 * free_area_init_node() 989 * 990 * An architecture is expected to register range of page frames backed by 991 * physical memory with add_active_range() before calling 992 * free_area_init_nodes() passing in the PFN each zone ends at. At a basic 993 * usage, an architecture is expected to do something like 994 * 995 * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn, 996 * max_highmem_pfn}; 997 * for_each_valid_physical_page_range() 998 * add_active_range(node_id, start_pfn, end_pfn) 999 * free_area_init_nodes(max_zone_pfns); 1000 * 1001 * If the architecture guarantees that there are no holes in the ranges 1002 * registered with add_active_range(), free_bootmem_active_regions() 1003 * will call free_bootmem_node() for each registered physical page range. 1004 * Similarly sparse_memory_present_with_active_regions() calls 1005 * memory_present() for each range when SPARSEMEM is enabled. 1006 * 1007 * See mm/page_alloc.c for more information on each function exposed by 1008 * CONFIG_ARCH_POPULATES_NODE_MAP 1009 */ 1010 extern void free_area_init_nodes(unsigned long *max_zone_pfn); 1011 extern void add_active_range(unsigned int nid, unsigned long start_pfn, 1012 unsigned long end_pfn); 1013 extern void remove_active_range(unsigned int nid, unsigned long start_pfn, 1014 unsigned long end_pfn); 1015 extern void remove_all_active_ranges(void); 1016 extern unsigned long absent_pages_in_range(unsigned long start_pfn, 1017 unsigned long end_pfn); 1018 extern void get_pfn_range_for_nid(unsigned int nid, 1019 unsigned long *start_pfn, unsigned long *end_pfn); 1020 extern unsigned long find_min_pfn_with_active_regions(void); 1021 extern void free_bootmem_with_active_regions(int nid, 1022 unsigned long max_low_pfn); 1023 typedef int (*work_fn_t)(unsigned long, unsigned long, void *); 1024 extern void work_with_active_regions(int nid, work_fn_t work_fn, void *data); 1025 extern void sparse_memory_present_with_active_regions(int nid); 1026 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ 1027 1028 #if !defined(CONFIG_ARCH_POPULATES_NODE_MAP) && \ 1029 !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) 1030 static inline int __early_pfn_to_nid(unsigned long pfn) 1031 { 1032 return 0; 1033 } 1034 #else 1035 /* please see mm/page_alloc.c */ 1036 extern int __meminit early_pfn_to_nid(unsigned long pfn); 1037 #ifdef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID 1038 /* there is a per-arch backend function. */ 1039 extern int __meminit __early_pfn_to_nid(unsigned long pfn); 1040 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */ 1041 #endif 1042 1043 extern void set_dma_reserve(unsigned long new_dma_reserve); 1044 extern void memmap_init_zone(unsigned long, int, unsigned long, 1045 unsigned long, enum memmap_context); 1046 extern void setup_per_zone_wmarks(void); 1047 extern void calculate_zone_inactive_ratio(struct zone *zone); 1048 extern void mem_init(void); 1049 extern void __init mmap_init(void); 1050 extern void show_mem(void); 1051 extern void si_meminfo(struct sysinfo * val); 1052 extern void si_meminfo_node(struct sysinfo *val, int nid); 1053 extern int after_bootmem; 1054 1055 #ifdef CONFIG_NUMA 1056 extern void setup_per_cpu_pageset(void); 1057 #else 1058 static inline void setup_per_cpu_pageset(void) {} 1059 #endif 1060 1061 /* nommu.c */ 1062 extern atomic_long_t mmap_pages_allocated; 1063 1064 /* prio_tree.c */ 1065 void vma_prio_tree_add(struct vm_area_struct *, struct vm_area_struct *old); 1066 void vma_prio_tree_insert(struct vm_area_struct *, struct prio_tree_root *); 1067 void vma_prio_tree_remove(struct vm_area_struct *, struct prio_tree_root *); 1068 struct vm_area_struct *vma_prio_tree_next(struct vm_area_struct *vma, 1069 struct prio_tree_iter *iter); 1070 1071 #define vma_prio_tree_foreach(vma, iter, root, begin, end) \ 1072 for (prio_tree_iter_init(iter, root, begin, end), vma = NULL; \ 1073 (vma = vma_prio_tree_next(vma, iter)); ) 1074 1075 static inline void vma_nonlinear_insert(struct vm_area_struct *vma, 1076 struct list_head *list) 1077 { 1078 vma->shared.vm_set.parent = NULL; 1079 list_add_tail(&vma->shared.vm_set.list, list); 1080 } 1081 1082 /* mmap.c */ 1083 extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin); 1084 extern void vma_adjust(struct vm_area_struct *vma, unsigned long start, 1085 unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert); 1086 extern struct vm_area_struct *vma_merge(struct mm_struct *, 1087 struct vm_area_struct *prev, unsigned long addr, unsigned long end, 1088 unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t, 1089 struct mempolicy *); 1090 extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *); 1091 extern int split_vma(struct mm_struct *, 1092 struct vm_area_struct *, unsigned long addr, int new_below); 1093 extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *); 1094 extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *, 1095 struct rb_node **, struct rb_node *); 1096 extern void unlink_file_vma(struct vm_area_struct *); 1097 extern struct vm_area_struct *copy_vma(struct vm_area_struct **, 1098 unsigned long addr, unsigned long len, pgoff_t pgoff); 1099 extern void exit_mmap(struct mm_struct *); 1100 1101 extern int mm_take_all_locks(struct mm_struct *mm); 1102 extern void mm_drop_all_locks(struct mm_struct *mm); 1103 1104 #ifdef CONFIG_PROC_FS 1105 /* From fs/proc/base.c. callers must _not_ hold the mm's exe_file_lock */ 1106 extern void added_exe_file_vma(struct mm_struct *mm); 1107 extern void removed_exe_file_vma(struct mm_struct *mm); 1108 #else 1109 static inline void added_exe_file_vma(struct mm_struct *mm) 1110 {} 1111 1112 static inline void removed_exe_file_vma(struct mm_struct *mm) 1113 {} 1114 #endif /* CONFIG_PROC_FS */ 1115 1116 extern int may_expand_vm(struct mm_struct *mm, unsigned long npages); 1117 extern int install_special_mapping(struct mm_struct *mm, 1118 unsigned long addr, unsigned long len, 1119 unsigned long flags, struct page **pages); 1120 1121 extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); 1122 1123 extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, 1124 unsigned long len, unsigned long prot, 1125 unsigned long flag, unsigned long pgoff); 1126 extern unsigned long mmap_region(struct file *file, unsigned long addr, 1127 unsigned long len, unsigned long flags, 1128 unsigned int vm_flags, unsigned long pgoff); 1129 1130 static inline unsigned long do_mmap(struct file *file, unsigned long addr, 1131 unsigned long len, unsigned long prot, 1132 unsigned long flag, unsigned long offset) 1133 { 1134 unsigned long ret = -EINVAL; 1135 if ((offset + PAGE_ALIGN(len)) < offset) 1136 goto out; 1137 if (!(offset & ~PAGE_MASK)) 1138 ret = do_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT); 1139 out: 1140 return ret; 1141 } 1142 1143 extern int do_munmap(struct mm_struct *, unsigned long, size_t); 1144 1145 extern unsigned long do_brk(unsigned long, unsigned long); 1146 1147 /* filemap.c */ 1148 extern unsigned long page_unuse(struct page *); 1149 extern void truncate_inode_pages(struct address_space *, loff_t); 1150 extern void truncate_inode_pages_range(struct address_space *, 1151 loff_t lstart, loff_t lend); 1152 1153 /* generic vm_area_ops exported for stackable file systems */ 1154 extern int filemap_fault(struct vm_area_struct *, struct vm_fault *); 1155 1156 /* mm/page-writeback.c */ 1157 int write_one_page(struct page *page, int wait); 1158 void task_dirty_inc(struct task_struct *tsk); 1159 1160 /* readahead.c */ 1161 #define VM_MAX_READAHEAD 128 /* kbytes */ 1162 #define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */ 1163 1164 int force_page_cache_readahead(struct address_space *mapping, struct file *filp, 1165 pgoff_t offset, unsigned long nr_to_read); 1166 1167 void page_cache_sync_readahead(struct address_space *mapping, 1168 struct file_ra_state *ra, 1169 struct file *filp, 1170 pgoff_t offset, 1171 unsigned long size); 1172 1173 void page_cache_async_readahead(struct address_space *mapping, 1174 struct file_ra_state *ra, 1175 struct file *filp, 1176 struct page *pg, 1177 pgoff_t offset, 1178 unsigned long size); 1179 1180 unsigned long max_sane_readahead(unsigned long nr); 1181 unsigned long ra_submit(struct file_ra_state *ra, 1182 struct address_space *mapping, 1183 struct file *filp); 1184 1185 /* Do stack extension */ 1186 extern int expand_stack(struct vm_area_struct *vma, unsigned long address); 1187 #ifdef CONFIG_IA64 1188 extern int expand_upwards(struct vm_area_struct *vma, unsigned long address); 1189 #endif 1190 extern int expand_stack_downwards(struct vm_area_struct *vma, 1191 unsigned long address); 1192 1193 /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */ 1194 extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr); 1195 extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr, 1196 struct vm_area_struct **pprev); 1197 1198 /* Look up the first VMA which intersects the interval start_addr..end_addr-1, 1199 NULL if none. Assume start_addr < end_addr. */ 1200 static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr) 1201 { 1202 struct vm_area_struct * vma = find_vma(mm,start_addr); 1203 1204 if (vma && end_addr <= vma->vm_start) 1205 vma = NULL; 1206 return vma; 1207 } 1208 1209 static inline unsigned long vma_pages(struct vm_area_struct *vma) 1210 { 1211 return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; 1212 } 1213 1214 pgprot_t vm_get_page_prot(unsigned long vm_flags); 1215 struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr); 1216 int remap_pfn_range(struct vm_area_struct *, unsigned long addr, 1217 unsigned long pfn, unsigned long size, pgprot_t); 1218 int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *); 1219 int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr, 1220 unsigned long pfn); 1221 int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr, 1222 unsigned long pfn); 1223 1224 struct page *follow_page(struct vm_area_struct *, unsigned long address, 1225 unsigned int foll_flags); 1226 #define FOLL_WRITE 0x01 /* check pte is writable */ 1227 #define FOLL_TOUCH 0x02 /* mark page accessed */ 1228 #define FOLL_GET 0x04 /* do get_page on page */ 1229 #define FOLL_ANON 0x08 /* give ZERO_PAGE if no pgtable */ 1230 1231 typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr, 1232 void *data); 1233 extern int apply_to_page_range(struct mm_struct *mm, unsigned long address, 1234 unsigned long size, pte_fn_t fn, void *data); 1235 1236 #ifdef CONFIG_PROC_FS 1237 void vm_stat_account(struct mm_struct *, unsigned long, struct file *, long); 1238 #else 1239 static inline void vm_stat_account(struct mm_struct *mm, 1240 unsigned long flags, struct file *file, long pages) 1241 { 1242 } 1243 #endif /* CONFIG_PROC_FS */ 1244 1245 #ifdef CONFIG_DEBUG_PAGEALLOC 1246 extern int debug_pagealloc_enabled; 1247 1248 extern void kernel_map_pages(struct page *page, int numpages, int enable); 1249 1250 static inline void enable_debug_pagealloc(void) 1251 { 1252 debug_pagealloc_enabled = 1; 1253 } 1254 #ifdef CONFIG_HIBERNATION 1255 extern bool kernel_page_present(struct page *page); 1256 #endif /* CONFIG_HIBERNATION */ 1257 #else 1258 static inline void 1259 kernel_map_pages(struct page *page, int numpages, int enable) {} 1260 static inline void enable_debug_pagealloc(void) 1261 { 1262 } 1263 #ifdef CONFIG_HIBERNATION 1264 static inline bool kernel_page_present(struct page *page) { return true; } 1265 #endif /* CONFIG_HIBERNATION */ 1266 #endif 1267 1268 extern struct vm_area_struct *get_gate_vma(struct task_struct *tsk); 1269 #ifdef __HAVE_ARCH_GATE_AREA 1270 int in_gate_area_no_task(unsigned long addr); 1271 int in_gate_area(struct task_struct *task, unsigned long addr); 1272 #else 1273 int in_gate_area_no_task(unsigned long addr); 1274 #define in_gate_area(task, addr) ({(void)task; in_gate_area_no_task(addr);}) 1275 #endif /* __HAVE_ARCH_GATE_AREA */ 1276 1277 int drop_caches_sysctl_handler(struct ctl_table *, int, struct file *, 1278 void __user *, size_t *, loff_t *); 1279 unsigned long shrink_slab(unsigned long scanned, gfp_t gfp_mask, 1280 unsigned long lru_pages); 1281 1282 #ifndef CONFIG_MMU 1283 #define randomize_va_space 0 1284 #else 1285 extern int randomize_va_space; 1286 #endif 1287 1288 const char * arch_vma_name(struct vm_area_struct *vma); 1289 void print_vma_addr(char *prefix, unsigned long rip); 1290 1291 struct page *sparse_mem_map_populate(unsigned long pnum, int nid); 1292 pgd_t *vmemmap_pgd_populate(unsigned long addr, int node); 1293 pud_t *vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node); 1294 pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node); 1295 pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node); 1296 void *vmemmap_alloc_block(unsigned long size, int node); 1297 void vmemmap_verify(pte_t *, int, unsigned long, unsigned long); 1298 int vmemmap_populate_basepages(struct page *start_page, 1299 unsigned long pages, int node); 1300 int vmemmap_populate(struct page *start_page, unsigned long pages, int node); 1301 void vmemmap_populate_print_last(void); 1302 1303 extern int account_locked_memory(struct mm_struct *mm, struct rlimit *rlim, 1304 size_t size); 1305 extern void refund_locked_memory(struct mm_struct *mm, size_t size); 1306 #endif /* __KERNEL__ */ 1307 #endif /* _LINUX_MM_H */ 1308