ia64/xen-unstable

view linux-2.4-xen-sparse/include/linux/mm.h @ 6538:84ee014ebd41

Merge xen-vtx-unstable.hg
author adsharma@los-vmm.sc.intel.com
date Wed Aug 17 12:34:38 2005 -0800 (2005-08-17)
parents 23979fb12c49 f294acb25858
children 99914b54f7bf
line source
1 #ifndef _LINUX_MM_H
2 #define _LINUX_MM_H
4 #include <linux/sched.h>
5 #include <linux/errno.h>
7 #ifdef __KERNEL__
9 #include <linux/config.h>
10 #include <linux/string.h>
11 #include <linux/list.h>
12 #include <linux/mmzone.h>
13 #include <linux/swap.h>
14 #include <linux/rbtree.h>
16 extern unsigned long max_mapnr;
17 extern unsigned long num_physpages;
18 extern unsigned long num_mappedpages;
19 extern void * high_memory;
20 extern int page_cluster;
21 /* The inactive_clean lists are per zone. */
22 extern struct list_head active_list;
23 extern struct list_head inactive_list;
25 #include <asm/page.h>
26 #include <asm/pgtable.h>
27 #include <asm/atomic.h>
29 /*
30 * Linux kernel virtual memory manager primitives.
31 * The idea being to have a "virtual" mm in the same way
32 * we have a virtual fs - giving a cleaner interface to the
33 * mm details, and allowing different kinds of memory mappings
34 * (from shared memory to executable loading to arbitrary
35 * mmap() functions).
36 */
38 /*
39 * This struct defines a memory VMM memory area. There is one of these
40 * per VM-area/task. A VM area is any part of the process virtual memory
41 * space that has a special rule for the page-fault handlers (ie a shared
42 * library, the executable area etc).
43 */
44 struct vm_area_struct {
45 struct mm_struct * vm_mm; /* The address space we belong to. */
46 unsigned long vm_start; /* Our start address within vm_mm. */
47 unsigned long vm_end; /* The first byte after our end address
48 within vm_mm. */
50 /* linked list of VM areas per task, sorted by address */
51 struct vm_area_struct *vm_next;
53 pgprot_t vm_page_prot; /* Access permissions of this VMA. */
54 unsigned long vm_flags; /* Flags, listed below. */
56 rb_node_t vm_rb;
58 /*
59 * For areas with an address space and backing store,
60 * one of the address_space->i_mmap{,shared} lists,
61 * for shm areas, the list of attaches, otherwise unused.
62 */
63 struct vm_area_struct *vm_next_share;
64 struct vm_area_struct **vm_pprev_share;
66 /* Function pointers to deal with this struct. */
67 struct vm_operations_struct * vm_ops;
69 /* Information about our backing store: */
70 unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE
71 units, *not* PAGE_CACHE_SIZE */
72 struct file * vm_file; /* File we map to (can be NULL). */
73 unsigned long vm_raend; /* XXX: put full readahead info here. */
74 void * vm_private_data; /* was vm_pte (shared mem) */
75 };
77 /*
78 * vm_flags..
79 */
80 #define VM_READ 0x00000001 /* currently active flags */
81 #define VM_WRITE 0x00000002
82 #define VM_EXEC 0x00000004
83 #define VM_SHARED 0x00000008
85 #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */
86 #define VM_MAYWRITE 0x00000020
87 #define VM_MAYEXEC 0x00000040
88 #define VM_MAYSHARE 0x00000080
90 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */
91 #define VM_GROWSUP 0x00000200
92 #define VM_SHM 0x00000400 /* shared memory area, don't swap out */
93 #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */
95 #define VM_EXECUTABLE 0x00001000
96 #define VM_LOCKED 0x00002000
97 #define VM_IO 0x00004000 /* Memory mapped I/O or similar */
99 /* Used by sys_madvise() */
100 #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */
101 #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */
103 #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */
104 #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */
105 #define VM_RESERVED 0x00080000 /* Don't unmap it from swap_out */
107 #ifndef VM_STACK_FLAGS
108 #define VM_STACK_FLAGS 0x00000177
109 #endif
111 #define VM_READHINTMASK (VM_SEQ_READ | VM_RAND_READ)
112 #define VM_ClearReadHint(v) (v)->vm_flags &= ~VM_READHINTMASK
113 #define VM_NormalReadHint(v) (!((v)->vm_flags & VM_READHINTMASK))
114 #define VM_SequentialReadHint(v) ((v)->vm_flags & VM_SEQ_READ)
115 #define VM_RandomReadHint(v) ((v)->vm_flags & VM_RAND_READ)
117 /* read ahead limits */
118 extern int vm_min_readahead;
119 extern int vm_max_readahead;
121 /*
122 * mapping from the currently active vm_flags protection bits (the
123 * low four bits) to a page protection mask..
124 */
125 extern pgprot_t protection_map[16];
128 /*
129 * These are the virtual MM functions - opening of an area, closing and
130 * unmapping it (needed to keep files on disk up-to-date etc), pointer
131 * to the functions called when a no-page or a wp-page exception occurs.
132 */
133 struct vm_operations_struct {
134 void (*open)(struct vm_area_struct * area);
135 void (*close)(struct vm_area_struct * area);
136 struct page * (*nopage)(struct vm_area_struct * area, unsigned long address, int unused);
137 };
139 /*
140 * Each physical page in the system has a struct page associated with
141 * it to keep track of whatever it is we are using the page for at the
142 * moment. Note that we have no way to track which tasks are using
143 * a page.
144 *
145 * Try to keep the most commonly accessed fields in single cache lines
146 * here (16 bytes or greater). This ordering should be particularly
147 * beneficial on 32-bit processors.
148 *
149 * The first line is data used in page cache lookup, the second line
150 * is used for linear searches (eg. clock algorithm scans).
151 *
152 * TODO: make this structure smaller, it could be as small as 32 bytes.
153 */
154 typedef struct page {
155 struct list_head list; /* ->mapping has some page lists. */
156 struct address_space *mapping; /* The inode (or ...) we belong to. */
157 unsigned long index; /* Our offset within mapping. */
158 struct page *next_hash; /* Next page sharing our hash bucket in
159 the pagecache hash table. */
160 atomic_t count; /* Usage count, see below. */
161 unsigned long flags; /* atomic flags, some possibly
162 updated asynchronously */
163 struct list_head lru; /* Pageout list, eg. active_list;
164 protected by pagemap_lru_lock !! */
165 struct page **pprev_hash; /* Complement to *next_hash. */
166 struct buffer_head * buffers; /* Buffer maps us to a disk block. */
168 /*
169 * On machines where all RAM is mapped into kernel address space,
170 * we can simply calculate the virtual address. On machines with
171 * highmem some memory is mapped into kernel virtual memory
172 * dynamically, so we need a place to store that address.
173 * Note that this field could be 16 bits on x86 ... ;)
174 *
175 * Architectures with slow multiplication can define
176 * WANT_PAGE_VIRTUAL in asm/page.h
177 */
178 #if defined(CONFIG_HIGHMEM) || defined(WANT_PAGE_VIRTUAL)
179 void *virtual; /* Kernel virtual address (NULL if
180 not kmapped, ie. highmem) */
181 #endif /* CONFIG_HIGMEM || WANT_PAGE_VIRTUAL */
182 } mem_map_t;
184 /*
185 * Methods to modify the page usage count.
186 *
187 * What counts for a page usage:
188 * - cache mapping (page->mapping)
189 * - disk mapping (page->buffers)
190 * - page mapped in a task's page tables, each mapping
191 * is counted separately
192 *
193 * Also, many kernel routines increase the page count before a critical
194 * routine so they can be sure the page doesn't go away from under them.
195 */
196 #define get_page(p) atomic_inc(&(p)->count)
197 #define put_page(p) __free_page(p)
198 #define put_page_testzero(p) atomic_dec_and_test(&(p)->count)
199 #define page_count(p) atomic_read(&(p)->count)
200 #define set_page_count(p,v) atomic_set(&(p)->count, v)
202 static inline struct page *nth_page(struct page *page, int n)
203 {
204 return page + n;
205 }
207 /*
208 * Various page->flags bits:
209 *
210 * PG_reserved is set for special pages, which can never be swapped
211 * out. Some of them might not even exist (eg empty_bad_page)...
212 *
213 * Multiple processes may "see" the same page. E.g. for untouched
214 * mappings of /dev/null, all processes see the same page full of
215 * zeroes, and text pages of executables and shared libraries have
216 * only one copy in memory, at most, normally.
217 *
218 * For the non-reserved pages, page->count denotes a reference count.
219 * page->count == 0 means the page is free.
220 * page->count == 1 means the page is used for exactly one purpose
221 * (e.g. a private data page of one process).
222 *
223 * A page may be used for kmalloc() or anyone else who does a
224 * __get_free_page(). In this case the page->count is at least 1, and
225 * all other fields are unused but should be 0 or NULL. The
226 * management of this page is the responsibility of the one who uses
227 * it.
228 *
229 * The other pages (we may call them "process pages") are completely
230 * managed by the Linux memory manager: I/O, buffers, swapping etc.
231 * The following discussion applies only to them.
232 *
233 * A page may belong to an inode's memory mapping. In this case,
234 * page->mapping is the pointer to the inode, and page->index is the
235 * file offset of the page, in units of PAGE_CACHE_SIZE.
236 *
237 * A page may have buffers allocated to it. In this case,
238 * page->buffers is a circular list of these buffer heads. Else,
239 * page->buffers == NULL.
240 *
241 * For pages belonging to inodes, the page->count is the number of
242 * attaches, plus 1 if buffers are allocated to the page, plus one
243 * for the page cache itself.
244 *
245 * All pages belonging to an inode are in these doubly linked lists:
246 * mapping->clean_pages, mapping->dirty_pages and mapping->locked_pages;
247 * using the page->list list_head. These fields are also used for
248 * freelist managemet (when page->count==0).
249 *
250 * There is also a hash table mapping (mapping,index) to the page
251 * in memory if present. The lists for this hash table use the fields
252 * page->next_hash and page->pprev_hash.
253 *
254 * All process pages can do I/O:
255 * - inode pages may need to be read from disk,
256 * - inode pages which have been modified and are MAP_SHARED may need
257 * to be written to disk,
258 * - private pages which have been modified may need to be swapped out
259 * to swap space and (later) to be read back into memory.
260 * During disk I/O, PG_locked is used. This bit is set before I/O
261 * and reset when I/O completes. page_waitqueue(page) is a wait queue of all
262 * tasks waiting for the I/O on this page to complete.
263 * PG_uptodate tells whether the page's contents is valid.
264 * When a read completes, the page becomes uptodate, unless a disk I/O
265 * error happened.
266 *
267 * For choosing which pages to swap out, inode pages carry a
268 * PG_referenced bit, which is set any time the system accesses
269 * that page through the (mapping,index) hash table. This referenced
270 * bit, together with the referenced bit in the page tables, is used
271 * to manipulate page->age and move the page across the active,
272 * inactive_dirty and inactive_clean lists.
273 *
274 * Note that the referenced bit, the page->lru list_head and the
275 * active, inactive_dirty and inactive_clean lists are protected by
276 * the pagemap_lru_lock, and *NOT* by the usual PG_locked bit!
277 *
278 * PG_skip is used on sparc/sparc64 architectures to "skip" certain
279 * parts of the address space.
280 *
281 * PG_error is set to indicate that an I/O error occurred on this page.
282 *
283 * PG_arch_1 is an architecture specific page state bit. The generic
284 * code guarantees that this bit is cleared for a page when it first
285 * is entered into the page cache.
286 *
287 * PG_highmem pages are not permanently mapped into the kernel virtual
288 * address space, they need to be kmapped separately for doing IO on
289 * the pages. The struct page (these bits with information) are always
290 * mapped into kernel address space...
291 */
292 #define PG_locked 0 /* Page is locked. Don't touch. */
293 #define PG_error 1
294 #define PG_referenced 2
295 #define PG_uptodate 3
296 #define PG_dirty 4
297 #define PG_unused 5
298 #define PG_lru 6
299 #define PG_active 7
300 #define PG_slab 8
301 #define PG_skip 10
302 #define PG_highmem 11
303 #define PG_checked 12 /* kill me in 2.5.<early>. */
304 #define PG_arch_1 13
305 #define PG_reserved 14
306 #define PG_launder 15 /* written out by VM pressure.. */
307 #define PG_fs_1 16 /* Filesystem specific */
308 #define PG_foreign 21 /* Page belongs to foreign allocator */
310 #ifndef arch_set_page_uptodate
311 #define arch_set_page_uptodate(page)
312 #endif
314 /* Make it prettier to test the above... */
315 #define UnlockPage(page) unlock_page(page)
316 #define Page_Uptodate(page) test_bit(PG_uptodate, &(page)->flags)
317 #ifndef SetPageUptodate
318 #define SetPageUptodate(page) set_bit(PG_uptodate, &(page)->flags)
319 #endif
320 #define ClearPageUptodate(page) clear_bit(PG_uptodate, &(page)->flags)
321 #define PageDirty(page) test_bit(PG_dirty, &(page)->flags)
322 #define SetPageDirty(page) set_bit(PG_dirty, &(page)->flags)
323 #define ClearPageDirty(page) clear_bit(PG_dirty, &(page)->flags)
324 #define PageLocked(page) test_bit(PG_locked, &(page)->flags)
325 #define LockPage(page) set_bit(PG_locked, &(page)->flags)
326 #define TryLockPage(page) test_and_set_bit(PG_locked, &(page)->flags)
327 #define PageChecked(page) test_bit(PG_checked, &(page)->flags)
328 #define SetPageChecked(page) set_bit(PG_checked, &(page)->flags)
329 #define ClearPageChecked(page) clear_bit(PG_checked, &(page)->flags)
330 #define PageLaunder(page) test_bit(PG_launder, &(page)->flags)
331 #define SetPageLaunder(page) set_bit(PG_launder, &(page)->flags)
332 #define ClearPageLaunder(page) clear_bit(PG_launder, &(page)->flags)
333 #define ClearPageArch1(page) clear_bit(PG_arch_1, &(page)->flags)
335 /* A foreign page uses a custom destructor rather than the buddy allocator. */
336 #ifdef CONFIG_FOREIGN_PAGES
337 #define PageForeign(page) test_bit(PG_foreign, &(page)->flags)
338 #define SetPageForeign(page, dtor) do { \
339 set_bit(PG_foreign, &(page)->flags); \
340 (page)->mapping = (void *)dtor; \
341 } while (0)
342 #define ClearPageForeign(page) do { \
343 clear_bit(PG_foreign, &(page)->flags); \
344 (page)->mapping = NULL; \
345 } while (0)
346 #define PageForeignDestructor(page) \
347 ( (void (*) (struct page *)) (page)->mapping )
348 #else
349 #define PageForeign(page) 0
350 #define PageForeignDestructor(page) void
351 #endif
353 /*
354 * The zone field is never updated after free_area_init_core()
355 * sets it, so none of the operations on it need to be atomic.
356 */
357 #define NODE_SHIFT 4
358 #define ZONE_SHIFT (BITS_PER_LONG - 8)
360 struct zone_struct;
361 extern struct zone_struct *zone_table[];
363 static inline zone_t *page_zone(struct page *page)
364 {
365 return zone_table[page->flags >> ZONE_SHIFT];
366 }
368 static inline void set_page_zone(struct page *page, unsigned long zone_num)
369 {
370 page->flags &= ~(~0UL << ZONE_SHIFT);
371 page->flags |= zone_num << ZONE_SHIFT;
372 }
374 /*
375 * In order to avoid #ifdefs within C code itself, we define
376 * set_page_address to a noop for non-highmem machines, where
377 * the field isn't useful.
378 * The same is true for page_address() in arch-dependent code.
379 */
380 #if defined(CONFIG_HIGHMEM) || defined(WANT_PAGE_VIRTUAL)
382 #define set_page_address(page, address) \
383 do { \
384 (page)->virtual = (address); \
385 } while(0)
387 #else /* CONFIG_HIGHMEM || WANT_PAGE_VIRTUAL */
388 #define set_page_address(page, address) do { } while(0)
389 #endif /* CONFIG_HIGHMEM || WANT_PAGE_VIRTUAL */
391 /*
392 * Permanent address of a page. Obviously must never be
393 * called on a highmem page.
394 */
395 #if defined(CONFIG_HIGHMEM) || defined(WANT_PAGE_VIRTUAL)
397 #define page_address(page) ((page)->virtual)
399 #else /* CONFIG_HIGHMEM || WANT_PAGE_VIRTUAL */
401 #define page_address(page) \
402 __va( (((page) - page_zone(page)->zone_mem_map) << PAGE_SHIFT) \
403 + page_zone(page)->zone_start_paddr)
405 #endif /* CONFIG_HIGHMEM || WANT_PAGE_VIRTUAL */
407 extern void FASTCALL(set_page_dirty(struct page *));
409 /*
410 * The first mb is necessary to safely close the critical section opened by the
411 * TryLockPage(), the second mb is necessary to enforce ordering between
412 * the clear_bit and the read of the waitqueue (to avoid SMP races with a
413 * parallel wait_on_page).
414 */
415 #define PageError(page) test_bit(PG_error, &(page)->flags)
416 #define SetPageError(page) set_bit(PG_error, &(page)->flags)
417 #define ClearPageError(page) clear_bit(PG_error, &(page)->flags)
418 #define PageReferenced(page) test_bit(PG_referenced, &(page)->flags)
419 #define SetPageReferenced(page) set_bit(PG_referenced, &(page)->flags)
420 #define ClearPageReferenced(page) clear_bit(PG_referenced, &(page)->flags)
421 #define PageTestandClearReferenced(page) test_and_clear_bit(PG_referenced, &(page)->flags)
422 #define PageSlab(page) test_bit(PG_slab, &(page)->flags)
423 #define PageSetSlab(page) set_bit(PG_slab, &(page)->flags)
424 #define PageClearSlab(page) clear_bit(PG_slab, &(page)->flags)
425 #define PageReserved(page) test_bit(PG_reserved, &(page)->flags)
427 #define PageActive(page) test_bit(PG_active, &(page)->flags)
428 #define SetPageActive(page) set_bit(PG_active, &(page)->flags)
429 #define ClearPageActive(page) clear_bit(PG_active, &(page)->flags)
431 #define PageLRU(page) test_bit(PG_lru, &(page)->flags)
432 #define TestSetPageLRU(page) test_and_set_bit(PG_lru, &(page)->flags)
433 #define TestClearPageLRU(page) test_and_clear_bit(PG_lru, &(page)->flags)
435 #ifdef CONFIG_HIGHMEM
436 #define PageHighMem(page) test_bit(PG_highmem, &(page)->flags)
437 #else
438 #define PageHighMem(page) 0 /* needed to optimize away at compile time */
439 #endif
441 #define SetPageReserved(page) set_bit(PG_reserved, &(page)->flags)
442 #define ClearPageReserved(page) clear_bit(PG_reserved, &(page)->flags)
444 /*
445 * Error return values for the *_nopage functions
446 */
447 #define NOPAGE_SIGBUS (NULL)
448 #define NOPAGE_OOM ((struct page *) (-1))
450 /* The array of struct pages */
451 extern mem_map_t * mem_map;
453 /*
454 * There is only one page-allocator function, and two main namespaces to
455 * it. The alloc_page*() variants return 'struct page *' and as such
456 * can allocate highmem pages, the *get*page*() variants return
457 * virtual kernel addresses to the allocated page(s).
458 */
459 extern struct page * FASTCALL(_alloc_pages(unsigned int gfp_mask, unsigned int order));
460 extern struct page * FASTCALL(__alloc_pages(unsigned int gfp_mask, unsigned int order, zonelist_t *zonelist));
461 extern struct page * alloc_pages_node(int nid, unsigned int gfp_mask, unsigned int order);
463 static inline struct page * alloc_pages(unsigned int gfp_mask, unsigned int order)
464 {
465 /*
466 * Gets optimized away by the compiler.
467 */
468 if (order >= MAX_ORDER)
469 return NULL;
470 return _alloc_pages(gfp_mask, order);
471 }
473 #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
475 extern unsigned long FASTCALL(__get_free_pages(unsigned int gfp_mask, unsigned int order));
476 extern unsigned long FASTCALL(get_zeroed_page(unsigned int gfp_mask));
478 #define __get_free_page(gfp_mask) \
479 __get_free_pages((gfp_mask),0)
481 #define __get_dma_pages(gfp_mask, order) \
482 __get_free_pages((gfp_mask) | GFP_DMA,(order))
484 /*
485 * The old interface name will be removed in 2.5:
486 */
487 #define get_free_page get_zeroed_page
489 /*
490 * There is only one 'core' page-freeing function.
491 */
492 extern void FASTCALL(__free_pages(struct page *page, unsigned int order));
493 extern void FASTCALL(free_pages(unsigned long addr, unsigned int order));
495 #define __free_page(page) __free_pages((page), 0)
496 #define free_page(addr) free_pages((addr),0)
498 extern void show_free_areas(void);
499 extern void show_free_areas_node(pg_data_t *pgdat);
501 extern void clear_page_tables(struct mm_struct *, unsigned long, int);
503 extern int fail_writepage(struct page *);
504 struct page * shmem_nopage(struct vm_area_struct * vma, unsigned long address, int unused);
505 struct file *shmem_file_setup(char * name, loff_t size);
506 extern void shmem_lock(struct file * file, int lock);
507 extern int shmem_zero_setup(struct vm_area_struct *);
509 extern void zap_page_range(struct mm_struct *mm, unsigned long address, unsigned long size);
510 extern int copy_page_range(struct mm_struct *dst, struct mm_struct *src, struct vm_area_struct *vma);
511 extern int remap_page_range(unsigned long from, unsigned long to, unsigned long size, pgprot_t prot);
512 extern int zeromap_page_range(unsigned long from, unsigned long size, pgprot_t prot);
514 extern int vmtruncate(struct inode * inode, loff_t offset);
515 extern pmd_t *FASTCALL(__pmd_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address));
516 extern pte_t *FASTCALL(pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address));
517 extern int handle_mm_fault(struct mm_struct *mm,struct vm_area_struct *vma, unsigned long address, int write_access);
518 extern int make_pages_present(unsigned long addr, unsigned long end);
519 extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write);
520 extern int ptrace_readdata(struct task_struct *tsk, unsigned long src, char *dst, int len);
521 extern int ptrace_writedata(struct task_struct *tsk, char * src, unsigned long dst, int len);
522 extern int ptrace_attach(struct task_struct *tsk);
523 extern int ptrace_detach(struct task_struct *, unsigned int);
524 extern void ptrace_disable(struct task_struct *);
525 extern int ptrace_check_attach(struct task_struct *task, int kill);
527 int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, unsigned long start,
528 int len, int write, int force, struct page **pages, struct vm_area_struct **vmas);
530 /*
531 * On a two-level page table, this ends up being trivial. Thus the
532 * inlining and the symmetry break with pte_alloc() that does all
533 * of this out-of-line.
534 */
535 static inline pmd_t *pmd_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
536 {
537 if (pgd_none(*pgd))
538 return __pmd_alloc(mm, pgd, address);
539 return pmd_offset(pgd, address);
540 }
542 extern int pgt_cache_water[2];
543 extern int check_pgt_cache(void);
545 extern void free_area_init(unsigned long * zones_size);
546 extern void free_area_init_node(int nid, pg_data_t *pgdat, struct page *pmap,
547 unsigned long * zones_size, unsigned long zone_start_paddr,
548 unsigned long *zholes_size);
549 extern void mem_init(void);
550 extern void show_mem(void);
551 extern void si_meminfo(struct sysinfo * val);
552 extern void swapin_readahead(swp_entry_t);
554 extern struct address_space swapper_space;
555 #define PageSwapCache(page) ((page)->mapping == &swapper_space)
557 static inline int is_page_cache_freeable(struct page * page)
558 {
559 return page_count(page) - !!page->buffers == 1;
560 }
562 extern int FASTCALL(can_share_swap_page(struct page *));
563 extern int FASTCALL(remove_exclusive_swap_page(struct page *));
565 extern void __free_pte(pte_t);
567 /* mmap.c */
568 extern void lock_vma_mappings(struct vm_area_struct *);
569 extern void unlock_vma_mappings(struct vm_area_struct *);
570 extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
571 extern void __insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
572 extern void build_mmap_rb(struct mm_struct *);
573 extern void exit_mmap(struct mm_struct *);
575 extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
577 extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
578 unsigned long len, unsigned long prot,
579 unsigned long flag, unsigned long pgoff);
581 static inline unsigned long do_mmap(struct file *file, unsigned long addr,
582 unsigned long len, unsigned long prot,
583 unsigned long flag, unsigned long offset)
584 {
585 unsigned long ret = -EINVAL;
586 if ((offset + PAGE_ALIGN(len)) < offset)
587 goto out;
588 if (!(offset & ~PAGE_MASK))
589 ret = do_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT);
590 out:
591 return ret;
592 }
594 extern int do_munmap(struct mm_struct *, unsigned long, size_t);
596 extern unsigned long do_brk(unsigned long, unsigned long);
598 static inline void __vma_unlink(struct mm_struct * mm, struct vm_area_struct * vma, struct vm_area_struct * prev)
599 {
600 prev->vm_next = vma->vm_next;
601 rb_erase(&vma->vm_rb, &mm->mm_rb);
602 if (mm->mmap_cache == vma)
603 mm->mmap_cache = prev;
604 }
606 static inline int can_vma_merge(struct vm_area_struct * vma, unsigned long vm_flags)
607 {
608 if (!vma->vm_file && vma->vm_flags == vm_flags)
609 return 1;
610 else
611 return 0;
612 }
614 struct zone_t;
615 /* filemap.c */
616 extern void remove_inode_page(struct page *);
617 extern unsigned long page_unuse(struct page *);
618 extern void truncate_inode_pages(struct address_space *, loff_t);
620 /* generic vm_area_ops exported for stackable file systems */
621 extern int filemap_sync(struct vm_area_struct *, unsigned long, size_t, unsigned int);
622 extern struct page *filemap_nopage(struct vm_area_struct *, unsigned long, int);
624 /*
625 * GFP bitmasks..
626 */
627 /* Zone modifiers in GFP_ZONEMASK (see linux/mmzone.h - low four bits) */
628 #define __GFP_DMA 0x01
629 #define __GFP_HIGHMEM 0x02
631 /* Action modifiers - doesn't change the zoning */
632 #define __GFP_WAIT 0x10 /* Can wait and reschedule? */
633 #define __GFP_HIGH 0x20 /* Should access emergency pools? */
634 #define __GFP_IO 0x40 /* Can start low memory physical IO? */
635 #define __GFP_HIGHIO 0x80 /* Can start high mem physical IO? */
636 #define __GFP_FS 0x100 /* Can call down to low-level FS? */
638 #define GFP_NOHIGHIO (__GFP_HIGH | __GFP_WAIT | __GFP_IO)
639 #define GFP_NOIO (__GFP_HIGH | __GFP_WAIT)
640 #define GFP_NOFS (__GFP_HIGH | __GFP_WAIT | __GFP_IO | __GFP_HIGHIO)
641 #define GFP_ATOMIC (__GFP_HIGH)
642 #define GFP_USER ( __GFP_WAIT | __GFP_IO | __GFP_HIGHIO | __GFP_FS)
643 #define GFP_HIGHUSER ( __GFP_WAIT | __GFP_IO | __GFP_HIGHIO | __GFP_FS | __GFP_HIGHMEM)
644 #define GFP_KERNEL (__GFP_HIGH | __GFP_WAIT | __GFP_IO | __GFP_HIGHIO | __GFP_FS)
645 #define GFP_NFS (__GFP_HIGH | __GFP_WAIT | __GFP_IO | __GFP_HIGHIO | __GFP_FS)
646 #define GFP_KSWAPD ( __GFP_WAIT | __GFP_IO | __GFP_HIGHIO | __GFP_FS)
648 /* Flag - indicates that the buffer will be suitable for DMA. Ignored on some
649 platforms, used as appropriate on others */
651 #define GFP_DMA __GFP_DMA
653 static inline unsigned int pf_gfp_mask(unsigned int gfp_mask)
654 {
655 /* avoid all memory balancing I/O methods if this task cannot block on I/O */
656 if (current->flags & PF_NOIO)
657 gfp_mask &= ~(__GFP_IO | __GFP_HIGHIO | __GFP_FS);
659 return gfp_mask;
660 }
662 /* vma is the first one with address < vma->vm_end,
663 * and even address < vma->vm_start. Have to extend vma. */
664 static inline int expand_stack(struct vm_area_struct * vma, unsigned long address)
665 {
666 unsigned long grow;
668 /*
669 * vma->vm_start/vm_end cannot change under us because the caller
670 * is required to hold the mmap_sem in read mode. We need the
671 * page_table_lock lock to serialize against concurrent expand_stacks.
672 */
673 address &= PAGE_MASK;
674 spin_lock(&vma->vm_mm->page_table_lock);
676 /* already expanded while we were spinning? */
677 if (vma->vm_start <= address) {
678 spin_unlock(&vma->vm_mm->page_table_lock);
679 return 0;
680 }
682 grow = (vma->vm_start - address) >> PAGE_SHIFT;
683 if (vma->vm_end - address > current->rlim[RLIMIT_STACK].rlim_cur ||
684 ((vma->vm_mm->total_vm + grow) << PAGE_SHIFT) > current->rlim[RLIMIT_AS].rlim_cur) {
685 spin_unlock(&vma->vm_mm->page_table_lock);
686 return -ENOMEM;
687 }
689 if ((vma->vm_flags & VM_LOCKED) &&
690 ((vma->vm_mm->locked_vm + grow) << PAGE_SHIFT) > current->rlim[RLIMIT_MEMLOCK].rlim_cur) {
691 spin_unlock(&vma->vm_mm->page_table_lock);
692 return -ENOMEM;
693 }
696 vma->vm_start = address;
697 vma->vm_pgoff -= grow;
698 vma->vm_mm->total_vm += grow;
699 if (vma->vm_flags & VM_LOCKED)
700 vma->vm_mm->locked_vm += grow;
701 spin_unlock(&vma->vm_mm->page_table_lock);
702 return 0;
703 }
705 /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */
706 extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr);
707 extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
708 struct vm_area_struct **pprev);
710 /* Look up the first VMA which intersects the interval start_addr..end_addr-1,
711 NULL if none. Assume start_addr < end_addr. */
712 static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr)
713 {
714 struct vm_area_struct * vma = find_vma(mm,start_addr);
716 if (vma && end_addr <= vma->vm_start)
717 vma = NULL;
718 return vma;
719 }
721 extern struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr);
723 extern struct page * vmalloc_to_page(void *addr);
725 #endif /* __KERNEL__ */
727 #endif