4 #include <linux/sched.h>
5 #include <linux/errno.h>
6 #include <linux/capability.h>
10 #include <linux/gfp.h>
11 #include <linux/list.h>
12 #include <linux/mmzone.h>
13 #include <linux/rbtree.h>
14 #include <linux/prio_tree.h>
16 #include <linux/mutex.h>
17 #include <linux/debug_locks.h>
18 #include <linux/backing-dev.h>
19 #include <linux/mm_types.h>
24 #ifndef CONFIG_DISCONTIGMEM /* Don't use mapnrs, do it properly */
25 extern unsigned long max_mapnr
;
28 extern unsigned long num_physpages
;
29 extern void * high_memory
;
30 extern unsigned long vmalloc_earlyreserve
;
31 extern int page_cluster
;
34 extern int sysctl_legacy_va_layout
;
36 #define sysctl_legacy_va_layout 0
40 #include <asm/pgtable.h>
41 #include <asm/processor.h>
43 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
46 * Linux kernel virtual memory manager primitives.
47 * The idea being to have a "virtual" mm in the same way
48 * we have a virtual fs - giving a cleaner interface to the
49 * mm details, and allowing different kinds of memory mappings
50 * (from shared memory to executable loading to arbitrary
55 * This struct defines a memory VMM memory area. There is one of these
56 * per VM-area/task. A VM area is any part of the process virtual memory
57 * space that has a special rule for the page-fault handlers (ie a shared
58 * library, the executable area etc).
60 struct vm_area_struct
{
61 struct mm_struct
* vm_mm
; /* The address space we belong to. */
62 unsigned long vm_start
; /* Our start address within vm_mm. */
63 unsigned long vm_end
; /* The first byte after our end address
66 /* linked list of VM areas per task, sorted by address */
67 struct vm_area_struct
*vm_next
;
69 pgprot_t vm_page_prot
; /* Access permissions of this VMA. */
70 unsigned long vm_flags
; /* Flags, listed below. */
75 * For areas with an address space and backing store,
76 * linkage into the address_space->i_mmap prio tree, or
77 * linkage to the list of like vmas hanging off its node, or
78 * linkage of vma in the address_space->i_mmap_nonlinear list.
82 struct list_head list
;
83 void *parent
; /* aligns with prio_tree_node parent */
84 struct vm_area_struct
*head
;
87 struct raw_prio_tree_node prio_tree_node
;
91 * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma
92 * list, after a COW of one of the file pages. A MAP_SHARED vma
93 * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack
94 * or brk vma (with NULL file) can only be in an anon_vma list.
96 struct list_head anon_vma_node
; /* Serialized by anon_vma->lock */
97 struct anon_vma
*anon_vma
; /* Serialized by page_table_lock */
99 /* Function pointers to deal with this struct. */
100 struct vm_operations_struct
* vm_ops
;
102 /* Information about our backing store: */
103 unsigned long vm_pgoff
; /* Offset (within vm_file) in PAGE_SIZE
104 units, *not* PAGE_CACHE_SIZE */
105 struct file
* vm_file
; /* File we map to (can be NULL). */
106 void * vm_private_data
; /* was vm_pte (shared mem) */
107 unsigned long vm_truncate_count
;/* truncate_count or restart_addr */
110 atomic_t vm_usage
; /* refcount (VMAs shared if !MMU) */
113 struct mempolicy
*vm_policy
; /* NUMA policy for the VMA */
117 extern struct kmem_cache
*vm_area_cachep
;
120 * This struct defines the per-mm list of VMAs for uClinux. If CONFIG_MMU is
121 * disabled, then there's a single shared list of VMAs maintained by the
122 * system, and mm's subscribe to these individually
124 struct vm_list_struct
{
125 struct vm_list_struct
*next
;
126 struct vm_area_struct
*vma
;
130 extern struct rb_root nommu_vma_tree
;
131 extern struct rw_semaphore nommu_vma_sem
;
133 extern unsigned int kobjsize(const void *objp
);
139 #define VM_READ 0x00000001 /* currently active flags */
140 #define VM_WRITE 0x00000002
141 #define VM_EXEC 0x00000004
142 #define VM_SHARED 0x00000008
144 /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */
145 #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */
146 #define VM_MAYWRITE 0x00000020
147 #define VM_MAYEXEC 0x00000040
148 #define VM_MAYSHARE 0x00000080
150 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */
151 #define VM_GROWSUP 0x00000200
152 #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */
153 #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */
155 #define VM_EXECUTABLE 0x00001000
156 #define VM_LOCKED 0x00002000
157 #define VM_IO 0x00004000 /* Memory mapped I/O or similar */
159 /* Used by sys_madvise() */
160 #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */
161 #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */
163 #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */
164 #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */
165 #define VM_RESERVED 0x00080000 /* Count as reserved_vm like IO */
166 #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */
167 #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */
168 #define VM_NONLINEAR 0x00800000 /* Is non-linear (remap_file_pages) */
169 #define VM_MAPPED_COPY 0x01000000 /* T if mapped copy of data (nommu mmap) */
170 #define VM_INSERTPAGE 0x02000000 /* The vma has had "vm_insert_page()" done on it */
171 #define VM_ALWAYSDUMP 0x04000000 /* Always include in core dumps */
173 #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */
174 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
177 #ifdef CONFIG_STACK_GROWSUP
178 #define VM_STACK_FLAGS (VM_GROWSUP | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
180 #define VM_STACK_FLAGS (VM_GROWSDOWN | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
183 #define VM_READHINTMASK (VM_SEQ_READ | VM_RAND_READ)
184 #define VM_ClearReadHint(v) (v)->vm_flags &= ~VM_READHINTMASK
185 #define VM_NormalReadHint(v) (!((v)->vm_flags & VM_READHINTMASK))
186 #define VM_SequentialReadHint(v) ((v)->vm_flags & VM_SEQ_READ)
187 #define VM_RandomReadHint(v) ((v)->vm_flags & VM_RAND_READ)
190 * mapping from the currently active vm_flags protection bits (the
191 * low four bits) to a page protection mask..
193 extern pgprot_t protection_map
[16];
197 * These are the virtual MM functions - opening of an area, closing and
198 * unmapping it (needed to keep files on disk up-to-date etc), pointer
199 * to the functions called when a no-page or a wp-page exception occurs.
201 struct vm_operations_struct
{
202 void (*open
)(struct vm_area_struct
* area
);
203 void (*close
)(struct vm_area_struct
* area
);
204 struct page
* (*nopage
)(struct vm_area_struct
* area
, unsigned long address
, int *type
);
205 unsigned long (*nopfn
)(struct vm_area_struct
* area
, unsigned long address
);
206 int (*populate
)(struct vm_area_struct
* area
, unsigned long address
, unsigned long len
, pgprot_t prot
, unsigned long pgoff
, int nonblock
);
208 /* notification that a previously read-only page is about to become
209 * writable, if an error is returned it will cause a SIGBUS */
210 int (*page_mkwrite
)(struct vm_area_struct
*vma
, struct page
*page
);
212 int (*set_policy
)(struct vm_area_struct
*vma
, struct mempolicy
*new);
213 struct mempolicy
*(*get_policy
)(struct vm_area_struct
*vma
,
215 int (*migrate
)(struct vm_area_struct
*vma
, const nodemask_t
*from
,
216 const nodemask_t
*to
, unsigned long flags
);
223 #define page_private(page) ((page)->private)
224 #define set_page_private(page, v) ((page)->private = (v))
227 * FIXME: take this include out, include page-flags.h in
228 * files which need it (119 of them)
230 #include <linux/page-flags.h>
232 #ifdef CONFIG_DEBUG_VM
233 #define VM_BUG_ON(cond) BUG_ON(cond)
235 #define VM_BUG_ON(condition) do { } while(0)
239 * Methods to modify the page usage count.
241 * What counts for a page usage:
242 * - cache mapping (page->mapping)
243 * - private data (page->private)
244 * - page mapped in a task's page tables, each mapping
245 * is counted separately
247 * Also, many kernel routines increase the page count before a critical
248 * routine so they can be sure the page doesn't go away from under them.
252 * Drop a ref, return true if the refcount fell to zero (the page has no users)
254 static inline int put_page_testzero(struct page
*page
)
256 VM_BUG_ON(atomic_read(&page
->_count
) == 0);
257 return atomic_dec_and_test(&page
->_count
);
261 * Try to grab a ref unless the page has a refcount of zero, return false if
264 static inline int get_page_unless_zero(struct page
*page
)
266 VM_BUG_ON(PageCompound(page
));
267 return atomic_inc_not_zero(&page
->_count
);
270 static inline int page_count(struct page
*page
)
272 if (unlikely(PageCompound(page
)))
273 page
= (struct page
*)page_private(page
);
274 return atomic_read(&page
->_count
);
277 static inline void get_page(struct page
*page
)
279 if (unlikely(PageCompound(page
)))
280 page
= (struct page
*)page_private(page
);
281 VM_BUG_ON(atomic_read(&page
->_count
) == 0);
282 atomic_inc(&page
->_count
);
286 * Setup the page count before being freed into the page allocator for
287 * the first time (boot or memory hotplug)
289 static inline void init_page_count(struct page
*page
)
291 atomic_set(&page
->_count
, 1);
294 void put_page(struct page
*page
);
295 void put_pages_list(struct list_head
*pages
);
297 void split_page(struct page
*page
, unsigned int order
);
300 * Compound pages have a destructor function. Provide a
301 * prototype for that function and accessor functions.
302 * These are _only_ valid on the head of a PG_compound page.
304 typedef void compound_page_dtor(struct page
*);
306 static inline void set_compound_page_dtor(struct page
*page
,
307 compound_page_dtor
*dtor
)
309 page
[1].lru
.next
= (void *)dtor
;
312 static inline compound_page_dtor
*get_compound_page_dtor(struct page
*page
)
314 return (compound_page_dtor
*)page
[1].lru
.next
;
318 * Multiple processes may "see" the same page. E.g. for untouched
319 * mappings of /dev/null, all processes see the same page full of
320 * zeroes, and text pages of executables and shared libraries have
321 * only one copy in memory, at most, normally.
323 * For the non-reserved pages, page_count(page) denotes a reference count.
324 * page_count() == 0 means the page is free. page->lru is then used for
325 * freelist management in the buddy allocator.
326 * page_count() > 0 means the page has been allocated.
328 * Pages are allocated by the slab allocator in order to provide memory
329 * to kmalloc and kmem_cache_alloc. In this case, the management of the
330 * page, and the fields in 'struct page' are the responsibility of mm/slab.c
331 * unless a particular usage is carefully commented. (the responsibility of
332 * freeing the kmalloc memory is the caller's, of course).
334 * A page may be used by anyone else who does a __get_free_page().
335 * In this case, page_count still tracks the references, and should only
336 * be used through the normal accessor functions. The top bits of page->flags
337 * and page->virtual store page management information, but all other fields
338 * are unused and could be used privately, carefully. The management of this
339 * page is the responsibility of the one who allocated it, and those who have
340 * subsequently been given references to it.
342 * The other pages (we may call them "pagecache pages") are completely
343 * managed by the Linux memory manager: I/O, buffers, swapping etc.
344 * The following discussion applies only to them.
346 * A pagecache page contains an opaque `private' member, which belongs to the
347 * page's address_space. Usually, this is the address of a circular list of
348 * the page's disk buffers. PG_private must be set to tell the VM to call
349 * into the filesystem to release these pages.
351 * A page may belong to an inode's memory mapping. In this case, page->mapping
352 * is the pointer to the inode, and page->index is the file offset of the page,
353 * in units of PAGE_CACHE_SIZE.
355 * If pagecache pages are not associated with an inode, they are said to be
356 * anonymous pages. These may become associated with the swapcache, and in that
357 * case PG_swapcache is set, and page->private is an offset into the swapcache.
359 * In either case (swapcache or inode backed), the pagecache itself holds one
360 * reference to the page. Setting PG_private should also increment the
361 * refcount. The each user mapping also has a reference to the page.
363 * The pagecache pages are stored in a per-mapping radix tree, which is
364 * rooted at mapping->page_tree, and indexed by offset.
365 * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space
366 * lists, we instead now tag pages as dirty/writeback in the radix tree.
368 * All pagecache pages may be subject to I/O:
369 * - inode pages may need to be read from disk,
370 * - inode pages which have been modified and are MAP_SHARED may need
371 * to be written back to the inode on disk,
372 * - anonymous pages (including MAP_PRIVATE file mappings) which have been
373 * modified may need to be swapped out to swap space and (later) to be read
378 * The zone field is never updated after free_area_init_core()
379 * sets it, so none of the operations on it need to be atomic.
384 * page->flags layout:
386 * There are three possibilities for how page->flags get
387 * laid out. The first is for the normal case, without
388 * sparsemem. The second is for sparsemem when there is
389 * plenty of space for node and section. The last is when
390 * we have run out of space and have to fall back to an
391 * alternate (slower) way of determining the node.
393 * No sparsemem: | NODE | ZONE | ... | FLAGS |
394 * with space for node: | SECTION | NODE | ZONE | ... | FLAGS |
395 * no space for node: | SECTION | ZONE | ... | FLAGS |
397 #ifdef CONFIG_SPARSEMEM
398 #define SECTIONS_WIDTH SECTIONS_SHIFT
400 #define SECTIONS_WIDTH 0
403 #define ZONES_WIDTH ZONES_SHIFT
405 #if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT <= FLAGS_RESERVED
406 #define NODES_WIDTH NODES_SHIFT
408 #define NODES_WIDTH 0
411 /* Page flags: | [SECTION] | [NODE] | ZONE | ... | FLAGS | */
412 #define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH)
413 #define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH)
414 #define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH)
417 * We are going to use the flags for the page to node mapping if its in
418 * there. This includes the case where there is no node, so it is implicit.
420 #if !(NODES_WIDTH > 0 || NODES_SHIFT == 0)
421 #define NODE_NOT_IN_PAGE_FLAGS
424 #ifndef PFN_SECTION_SHIFT
425 #define PFN_SECTION_SHIFT 0
429 * Define the bit shifts to access each section. For non-existant
430 * sections we define the shift as 0; that plus a 0 mask ensures
431 * the compiler will optimise away reference to them.
433 #define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0))
434 #define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0))
435 #define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0))
437 /* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allcator */
438 #ifdef NODE_NOT_IN_PAGEFLAGS
439 #define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT)
440 #define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF)? \
441 SECTIONS_PGOFF : ZONES_PGOFF)
443 #define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT)
444 #define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF)? \
445 NODES_PGOFF : ZONES_PGOFF)
448 #define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0))
450 #if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > FLAGS_RESERVED
451 #error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > FLAGS_RESERVED
454 #define ZONES_MASK ((1UL << ZONES_WIDTH) - 1)
455 #define NODES_MASK ((1UL << NODES_WIDTH) - 1)
456 #define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1)
457 #define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1)
459 static inline enum zone_type
page_zonenum(struct page
*page
)
461 return (page
->flags
>> ZONES_PGSHIFT
) & ZONES_MASK
;
465 * The identification function is only used by the buddy allocator for
466 * determining if two pages could be buddies. We are not really
467 * identifying a zone since we could be using a the section number
468 * id if we have not node id available in page flags.
469 * We guarantee only that it will return the same value for two
470 * combinable pages in a zone.
472 static inline int page_zone_id(struct page
*page
)
474 return (page
->flags
>> ZONEID_PGSHIFT
) & ZONEID_MASK
;
477 static inline int zone_to_nid(struct zone
*zone
)
486 #ifdef NODE_NOT_IN_PAGE_FLAGS
487 extern int page_to_nid(struct page
*page
);
489 static inline int page_to_nid(struct page
*page
)
491 return (page
->flags
>> NODES_PGSHIFT
) & NODES_MASK
;
495 static inline struct zone
*page_zone(struct page
*page
)
497 return &NODE_DATA(page_to_nid(page
))->node_zones
[page_zonenum(page
)];
500 static inline unsigned long page_to_section(struct page
*page
)
502 return (page
->flags
>> SECTIONS_PGSHIFT
) & SECTIONS_MASK
;
505 static inline void set_page_zone(struct page
*page
, enum zone_type zone
)
507 page
->flags
&= ~(ZONES_MASK
<< ZONES_PGSHIFT
);
508 page
->flags
|= (zone
& ZONES_MASK
) << ZONES_PGSHIFT
;
511 static inline void set_page_node(struct page
*page
, unsigned long node
)
513 page
->flags
&= ~(NODES_MASK
<< NODES_PGSHIFT
);
514 page
->flags
|= (node
& NODES_MASK
) << NODES_PGSHIFT
;
517 static inline void set_page_section(struct page
*page
, unsigned long section
)
519 page
->flags
&= ~(SECTIONS_MASK
<< SECTIONS_PGSHIFT
);
520 page
->flags
|= (section
& SECTIONS_MASK
) << SECTIONS_PGSHIFT
;
523 static inline void set_page_links(struct page
*page
, enum zone_type zone
,
524 unsigned long node
, unsigned long pfn
)
526 set_page_zone(page
, zone
);
527 set_page_node(page
, node
);
528 set_page_section(page
, pfn_to_section_nr(pfn
));
532 * Some inline functions in vmstat.h depend on page_zone()
534 #include <linux/vmstat.h>
536 static __always_inline
void *lowmem_page_address(struct page
*page
)
538 return __va(page_to_pfn(page
) << PAGE_SHIFT
);
541 #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
542 #define HASHED_PAGE_VIRTUAL
545 #if defined(WANT_PAGE_VIRTUAL)
546 #define page_address(page) ((page)->virtual)
547 #define set_page_address(page, address) \
549 (page)->virtual = (address); \
551 #define page_address_init() do { } while(0)
554 #if defined(HASHED_PAGE_VIRTUAL)
555 void *page_address(struct page
*page
);
556 void set_page_address(struct page
*page
, void *virtual);
557 void page_address_init(void);
560 #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
561 #define page_address(page) lowmem_page_address(page)
562 #define set_page_address(page, address) do { } while(0)
563 #define page_address_init() do { } while(0)
567 * On an anonymous page mapped into a user virtual memory area,
568 * page->mapping points to its anon_vma, not to a struct address_space;
569 * with the PAGE_MAPPING_ANON bit set to distinguish it.
571 * Please note that, confusingly, "page_mapping" refers to the inode
572 * address_space which maps the page from disk; whereas "page_mapped"
573 * refers to user virtual address space into which the page is mapped.
575 #define PAGE_MAPPING_ANON 1
577 extern struct address_space swapper_space
;
578 static inline struct address_space
*page_mapping(struct page
*page
)
580 struct address_space
*mapping
= page
->mapping
;
582 if (unlikely(PageSwapCache(page
)))
583 mapping
= &swapper_space
;
584 else if (unlikely((unsigned long)mapping
& PAGE_MAPPING_ANON
))
589 static inline int PageAnon(struct page
*page
)
591 return ((unsigned long)page
->mapping
& PAGE_MAPPING_ANON
) != 0;
595 * Return the pagecache index of the passed page. Regular pagecache pages
596 * use ->index whereas swapcache pages use ->private
598 static inline pgoff_t
page_index(struct page
*page
)
600 if (unlikely(PageSwapCache(page
)))
601 return page_private(page
);
606 * The atomic page->_mapcount, like _count, starts from -1:
607 * so that transitions both from it and to it can be tracked,
608 * using atomic_inc_and_test and atomic_add_negative(-1).
610 static inline void reset_page_mapcount(struct page
*page
)
612 atomic_set(&(page
)->_mapcount
, -1);
615 static inline int page_mapcount(struct page
*page
)
617 return atomic_read(&(page
)->_mapcount
) + 1;
621 * Return true if this page is mapped into pagetables.
623 static inline int page_mapped(struct page
*page
)
625 return atomic_read(&(page
)->_mapcount
) >= 0;
629 * Error return values for the *_nopage functions
631 #define NOPAGE_SIGBUS (NULL)
632 #define NOPAGE_OOM ((struct page *) (-1))
633 #define NOPAGE_REFAULT ((struct page *) (-2)) /* Return to userspace, rerun */
636 * Error return values for the *_nopfn functions
638 #define NOPFN_SIGBUS ((unsigned long) -1)
639 #define NOPFN_OOM ((unsigned long) -2)
640 #define NOPFN_REFAULT ((unsigned long) -3)
643 * Different kinds of faults, as returned by handle_mm_fault().
644 * Used to decide whether a process gets delivered SIGBUS or
645 * just gets major/minor fault counters bumped up.
647 #define VM_FAULT_OOM 0x00
648 #define VM_FAULT_SIGBUS 0x01
649 #define VM_FAULT_MINOR 0x02
650 #define VM_FAULT_MAJOR 0x03
653 * Special case for get_user_pages.
654 * Must be in a distinct bit from the above VM_FAULT_ flags.
656 #define VM_FAULT_WRITE 0x10
658 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
660 extern void show_free_areas(void);
663 struct page
*shmem_nopage(struct vm_area_struct
*vma
,
664 unsigned long address
, int *type
);
665 int shmem_set_policy(struct vm_area_struct
*vma
, struct mempolicy
*new);
666 struct mempolicy
*shmem_get_policy(struct vm_area_struct
*vma
,
668 int shmem_lock(struct file
*file
, int lock
, struct user_struct
*user
);
670 #define shmem_nopage filemap_nopage
672 static inline int shmem_lock(struct file
*file
, int lock
,
673 struct user_struct
*user
)
678 static inline int shmem_set_policy(struct vm_area_struct
*vma
,
679 struct mempolicy
*new)
684 static inline struct mempolicy
*shmem_get_policy(struct vm_area_struct
*vma
,
690 struct file
*shmem_file_setup(char *name
, loff_t size
, unsigned long flags
);
691 extern int shmem_mmap(struct file
*file
, struct vm_area_struct
*vma
);
693 int shmem_zero_setup(struct vm_area_struct
*);
696 extern unsigned long shmem_get_unmapped_area(struct file
*file
,
700 unsigned long flags
);
703 static inline int can_do_mlock(void)
705 if (capable(CAP_IPC_LOCK
))
707 if (current
->signal
->rlim
[RLIMIT_MEMLOCK
].rlim_cur
!= 0)
711 extern int user_shm_lock(size_t, struct user_struct
*);
712 extern void user_shm_unlock(size_t, struct user_struct
*);
715 * Parameter block passed down to zap_pte_range in exceptional cases.
718 struct vm_area_struct
*nonlinear_vma
; /* Check page->index if set */
719 struct address_space
*check_mapping
; /* Check page->mapping if set */
720 pgoff_t first_index
; /* Lowest page->index to unmap */
721 pgoff_t last_index
; /* Highest page->index to unmap */
722 spinlock_t
*i_mmap_lock
; /* For unmap_mapping_range: */
723 unsigned long truncate_count
; /* Compare vm_truncate_count */
726 struct page
*vm_normal_page(struct vm_area_struct
*, unsigned long, pte_t
);
727 unsigned long zap_page_range(struct vm_area_struct
*vma
, unsigned long address
,
728 unsigned long size
, struct zap_details
*);
729 unsigned long unmap_vmas(struct mmu_gather
**tlb
,
730 struct vm_area_struct
*start_vma
, unsigned long start_addr
,
731 unsigned long end_addr
, unsigned long *nr_accounted
,
732 struct zap_details
*);
733 void free_pgd_range(struct mmu_gather
**tlb
, unsigned long addr
,
734 unsigned long end
, unsigned long floor
, unsigned long ceiling
);
735 void free_pgtables(struct mmu_gather
**tlb
, struct vm_area_struct
*start_vma
,
736 unsigned long floor
, unsigned long ceiling
);
737 int copy_page_range(struct mm_struct
*dst
, struct mm_struct
*src
,
738 struct vm_area_struct
*vma
);
739 int zeromap_page_range(struct vm_area_struct
*vma
, unsigned long from
,
740 unsigned long size
, pgprot_t prot
);
741 void unmap_mapping_range(struct address_space
*mapping
,
742 loff_t
const holebegin
, loff_t
const holelen
, int even_cows
);
744 static inline void unmap_shared_mapping_range(struct address_space
*mapping
,
745 loff_t
const holebegin
, loff_t
const holelen
)
747 unmap_mapping_range(mapping
, holebegin
, holelen
, 0);
750 extern int vmtruncate(struct inode
* inode
, loff_t offset
);
751 extern int vmtruncate_range(struct inode
* inode
, loff_t offset
, loff_t end
);
752 extern int install_page(struct mm_struct
*mm
, struct vm_area_struct
*vma
, unsigned long addr
, struct page
*page
, pgprot_t prot
);
753 extern int install_file_pte(struct mm_struct
*mm
, struct vm_area_struct
*vma
, unsigned long addr
, unsigned long pgoff
, pgprot_t prot
);
756 extern int __handle_mm_fault(struct mm_struct
*mm
,struct vm_area_struct
*vma
,
757 unsigned long address
, int write_access
);
759 static inline int handle_mm_fault(struct mm_struct
*mm
,
760 struct vm_area_struct
*vma
, unsigned long address
,
763 return __handle_mm_fault(mm
, vma
, address
, write_access
) &
767 static inline int handle_mm_fault(struct mm_struct
*mm
,
768 struct vm_area_struct
*vma
, unsigned long address
,
771 /* should never happen if there's no MMU */
773 return VM_FAULT_SIGBUS
;
777 extern int make_pages_present(unsigned long addr
, unsigned long end
);
778 extern int access_process_vm(struct task_struct
*tsk
, unsigned long addr
, void *buf
, int len
, int write
);
779 void install_arg_page(struct vm_area_struct
*, struct page
*, unsigned long);
781 int get_user_pages(struct task_struct
*tsk
, struct mm_struct
*mm
, unsigned long start
,
782 int len
, int write
, int force
, struct page
**pages
, struct vm_area_struct
**vmas
);
783 void print_bad_pte(struct vm_area_struct
*, pte_t
, unsigned long);
785 extern int try_to_release_page(struct page
* page
, gfp_t gfp_mask
);
786 extern void do_invalidatepage(struct page
*page
, unsigned long offset
);
788 int __set_page_dirty_nobuffers(struct page
*page
);
789 int __set_page_dirty_no_writeback(struct page
*page
);
790 int redirty_page_for_writepage(struct writeback_control
*wbc
,
792 int FASTCALL(set_page_dirty(struct page
*page
));
793 int set_page_dirty_lock(struct page
*page
);
794 int clear_page_dirty_for_io(struct page
*page
);
796 extern unsigned long do_mremap(unsigned long addr
,
797 unsigned long old_len
, unsigned long new_len
,
798 unsigned long flags
, unsigned long new_addr
);
801 * Prototype to add a shrinker callback for ageable caches.
803 * These functions are passed a count `nr_to_scan' and a gfpmask. They should
804 * scan `nr_to_scan' objects, attempting to free them.
806 * The callback must return the number of objects which remain in the cache.
808 * The callback will be passed nr_to_scan == 0 when the VM is querying the
809 * cache size, so a fastpath for that case is appropriate.
811 typedef int (*shrinker_t
)(int nr_to_scan
, gfp_t gfp_mask
);
814 * Add an aging callback. The int is the number of 'seeks' it takes
815 * to recreate one of the objects that these functions age.
818 #define DEFAULT_SEEKS 2
820 extern struct shrinker
*set_shrinker(int, shrinker_t
);
821 extern void remove_shrinker(struct shrinker
*shrinker
);
824 * Some shared mappigns will want the pages marked read-only
825 * to track write events. If so, we'll downgrade vm_page_prot
826 * to the private version (using protection_map[] without the
829 static inline int vma_wants_writenotify(struct vm_area_struct
*vma
)
831 unsigned int vm_flags
= vma
->vm_flags
;
833 /* If it was private or non-writable, the write bit is already clear */
834 if ((vm_flags
& (VM_WRITE
|VM_SHARED
)) != ((VM_WRITE
|VM_SHARED
)))
837 /* The backer wishes to know when pages are first written to? */
838 if (vma
->vm_ops
&& vma
->vm_ops
->page_mkwrite
)
841 /* The open routine did something to the protections already? */
842 if (pgprot_val(vma
->vm_page_prot
) !=
843 pgprot_val(protection_map
[vm_flags
&
844 (VM_READ
|VM_WRITE
|VM_EXEC
|VM_SHARED
)]))
847 /* Specialty mapping? */
848 if (vm_flags
& (VM_PFNMAP
|VM_INSERTPAGE
))
851 /* Can the mapping track the dirty pages? */
852 return vma
->vm_file
&& vma
->vm_file
->f_mapping
&&
853 mapping_cap_account_dirty(vma
->vm_file
->f_mapping
);
856 extern pte_t
*FASTCALL(get_locked_pte(struct mm_struct
*mm
, unsigned long addr
, spinlock_t
**ptl
));
858 int __pud_alloc(struct mm_struct
*mm
, pgd_t
*pgd
, unsigned long address
);
859 int __pmd_alloc(struct mm_struct
*mm
, pud_t
*pud
, unsigned long address
);
860 int __pte_alloc(struct mm_struct
*mm
, pmd_t
*pmd
, unsigned long address
);
861 int __pte_alloc_kernel(pmd_t
*pmd
, unsigned long address
);
864 * The following ifdef needed to get the 4level-fixup.h header to work.
865 * Remove it when 4level-fixup.h has been removed.
867 #if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK)
868 static inline pud_t
*pud_alloc(struct mm_struct
*mm
, pgd_t
*pgd
, unsigned long address
)
870 return (unlikely(pgd_none(*pgd
)) && __pud_alloc(mm
, pgd
, address
))?
871 NULL
: pud_offset(pgd
, address
);
874 static inline pmd_t
*pmd_alloc(struct mm_struct
*mm
, pud_t
*pud
, unsigned long address
)
876 return (unlikely(pud_none(*pud
)) && __pmd_alloc(mm
, pud
, address
))?
877 NULL
: pmd_offset(pud
, address
);
879 #endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */
881 #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
883 * We tuck a spinlock to guard each pagetable page into its struct page,
884 * at page->private, with BUILD_BUG_ON to make sure that this will not
885 * overflow into the next struct page (as it might with DEBUG_SPINLOCK).
886 * When freeing, reset page->mapping so free_pages_check won't complain.
888 #define __pte_lockptr(page) &((page)->ptl)
889 #define pte_lock_init(_page) do { \
890 spin_lock_init(__pte_lockptr(_page)); \
892 #define pte_lock_deinit(page) ((page)->mapping = NULL)
893 #define pte_lockptr(mm, pmd) ({(void)(mm); __pte_lockptr(pmd_page(*(pmd)));})
896 * We use mm->page_table_lock to guard all pagetable pages of the mm.
898 #define pte_lock_init(page) do {} while (0)
899 #define pte_lock_deinit(page) do {} while (0)
900 #define pte_lockptr(mm, pmd) ({(void)(pmd); &(mm)->page_table_lock;})
901 #endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
903 #define pte_offset_map_lock(mm, pmd, address, ptlp) \
905 spinlock_t *__ptl = pte_lockptr(mm, pmd); \
906 pte_t *__pte = pte_offset_map(pmd, address); \
912 #define pte_unmap_unlock(pte, ptl) do { \
917 #define pte_alloc_map(mm, pmd, address) \
918 ((unlikely(!pmd_present(*(pmd))) && __pte_alloc(mm, pmd, address))? \
919 NULL: pte_offset_map(pmd, address))
921 #define pte_alloc_map_lock(mm, pmd, address, ptlp) \
922 ((unlikely(!pmd_present(*(pmd))) && __pte_alloc(mm, pmd, address))? \
923 NULL: pte_offset_map_lock(mm, pmd, address, ptlp))
925 #define pte_alloc_kernel(pmd, address) \
926 ((unlikely(!pmd_present(*(pmd))) && __pte_alloc_kernel(pmd, address))? \
927 NULL: pte_offset_kernel(pmd, address))
929 extern void free_area_init(unsigned long * zones_size
);
930 extern void free_area_init_node(int nid
, pg_data_t
*pgdat
,
931 unsigned long * zones_size
, unsigned long zone_start_pfn
,
932 unsigned long *zholes_size
);
933 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
935 * With CONFIG_ARCH_POPULATES_NODE_MAP set, an architecture may initialise its
936 * zones, allocate the backing mem_map and account for memory holes in a more
937 * architecture independent manner. This is a substitute for creating the
938 * zone_sizes[] and zholes_size[] arrays and passing them to
939 * free_area_init_node()
941 * An architecture is expected to register range of page frames backed by
942 * physical memory with add_active_range() before calling
943 * free_area_init_nodes() passing in the PFN each zone ends at. At a basic
944 * usage, an architecture is expected to do something like
946 * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn,
948 * for_each_valid_physical_page_range()
949 * add_active_range(node_id, start_pfn, end_pfn)
950 * free_area_init_nodes(max_zone_pfns);
952 * If the architecture guarantees that there are no holes in the ranges
953 * registered with add_active_range(), free_bootmem_active_regions()
954 * will call free_bootmem_node() for each registered physical page range.
955 * Similarly sparse_memory_present_with_active_regions() calls
956 * memory_present() for each range when SPARSEMEM is enabled.
958 * See mm/page_alloc.c for more information on each function exposed by
959 * CONFIG_ARCH_POPULATES_NODE_MAP
961 extern void free_area_init_nodes(unsigned long *max_zone_pfn
);
962 extern void add_active_range(unsigned int nid
, unsigned long start_pfn
,
963 unsigned long end_pfn
);
964 extern void shrink_active_range(unsigned int nid
, unsigned long old_end_pfn
,
965 unsigned long new_end_pfn
);
966 extern void push_node_boundaries(unsigned int nid
, unsigned long start_pfn
,
967 unsigned long end_pfn
);
968 extern void remove_all_active_ranges(void);
969 extern unsigned long absent_pages_in_range(unsigned long start_pfn
,
970 unsigned long end_pfn
);
971 extern void get_pfn_range_for_nid(unsigned int nid
,
972 unsigned long *start_pfn
, unsigned long *end_pfn
);
973 extern unsigned long find_min_pfn_with_active_regions(void);
974 extern unsigned long find_max_pfn_with_active_regions(void);
975 extern void free_bootmem_with_active_regions(int nid
,
976 unsigned long max_low_pfn
);
977 extern void sparse_memory_present_with_active_regions(int nid
);
978 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
979 extern int early_pfn_to_nid(unsigned long pfn
);
980 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
981 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
982 extern void set_dma_reserve(unsigned long new_dma_reserve
);
983 extern void memmap_init_zone(unsigned long, int, unsigned long,
984 unsigned long, enum memmap_context
);
985 extern void setup_per_zone_pages_min(void);
986 extern void mem_init(void);
987 extern void show_mem(void);
988 extern void si_meminfo(struct sysinfo
* val
);
989 extern void si_meminfo_node(struct sysinfo
*val
, int nid
);
992 extern void setup_per_cpu_pageset(void);
994 static inline void setup_per_cpu_pageset(void) {}
998 void vma_prio_tree_add(struct vm_area_struct
*, struct vm_area_struct
*old
);
999 void vma_prio_tree_insert(struct vm_area_struct
*, struct prio_tree_root
*);
1000 void vma_prio_tree_remove(struct vm_area_struct
*, struct prio_tree_root
*);
1001 struct vm_area_struct
*vma_prio_tree_next(struct vm_area_struct
*vma
,
1002 struct prio_tree_iter
*iter
);
1004 #define vma_prio_tree_foreach(vma, iter, root, begin, end) \
1005 for (prio_tree_iter_init(iter, root, begin, end), vma = NULL; \
1006 (vma = vma_prio_tree_next(vma, iter)); )
1008 static inline void vma_nonlinear_insert(struct vm_area_struct
*vma
,
1009 struct list_head
*list
)
1011 vma
->shared
.vm_set
.parent
= NULL
;
1012 list_add_tail(&vma
->shared
.vm_set
.list
, list
);
1016 extern int __vm_enough_memory(long pages
, int cap_sys_admin
);
1017 extern void vma_adjust(struct vm_area_struct
*vma
, unsigned long start
,
1018 unsigned long end
, pgoff_t pgoff
, struct vm_area_struct
*insert
);
1019 extern struct vm_area_struct
*vma_merge(struct mm_struct
*,
1020 struct vm_area_struct
*prev
, unsigned long addr
, unsigned long end
,
1021 unsigned long vm_flags
, struct anon_vma
*, struct file
*, pgoff_t
,
1022 struct mempolicy
*);
1023 extern struct anon_vma
*find_mergeable_anon_vma(struct vm_area_struct
*);
1024 extern int split_vma(struct mm_struct
*,
1025 struct vm_area_struct
*, unsigned long addr
, int new_below
);
1026 extern int insert_vm_struct(struct mm_struct
*, struct vm_area_struct
*);
1027 extern void __vma_link_rb(struct mm_struct
*, struct vm_area_struct
*,
1028 struct rb_node
**, struct rb_node
*);
1029 extern void unlink_file_vma(struct vm_area_struct
*);
1030 extern struct vm_area_struct
*copy_vma(struct vm_area_struct
**,
1031 unsigned long addr
, unsigned long len
, pgoff_t pgoff
);
1032 extern void exit_mmap(struct mm_struct
*);
1033 extern int may_expand_vm(struct mm_struct
*mm
, unsigned long npages
);
1034 extern int install_special_mapping(struct mm_struct
*mm
,
1035 unsigned long addr
, unsigned long len
,
1036 unsigned long flags
, struct page
**pages
);
1038 extern unsigned long get_unmapped_area(struct file
*, unsigned long, unsigned long, unsigned long, unsigned long);
1040 extern unsigned long do_mmap_pgoff(struct file
*file
, unsigned long addr
,
1041 unsigned long len
, unsigned long prot
,
1042 unsigned long flag
, unsigned long pgoff
);
1044 static inline unsigned long do_mmap(struct file
*file
, unsigned long addr
,
1045 unsigned long len
, unsigned long prot
,
1046 unsigned long flag
, unsigned long offset
)
1048 unsigned long ret
= -EINVAL
;
1049 if ((offset
+ PAGE_ALIGN(len
)) < offset
)
1051 if (!(offset
& ~PAGE_MASK
))
1052 ret
= do_mmap_pgoff(file
, addr
, len
, prot
, flag
, offset
>> PAGE_SHIFT
);
1057 extern int do_munmap(struct mm_struct
*, unsigned long, size_t);
1059 extern unsigned long do_brk(unsigned long, unsigned long);
1062 extern unsigned long page_unuse(struct page
*);
1063 extern void truncate_inode_pages(struct address_space
*, loff_t
);
1064 extern void truncate_inode_pages_range(struct address_space
*,
1065 loff_t lstart
, loff_t lend
);
1067 /* generic vm_area_ops exported for stackable file systems */
1068 extern struct page
*filemap_nopage(struct vm_area_struct
*, unsigned long, int *);
1069 extern int filemap_populate(struct vm_area_struct
*, unsigned long,
1070 unsigned long, pgprot_t
, unsigned long, int);
1072 /* mm/page-writeback.c */
1073 int write_one_page(struct page
*page
, int wait
);
1076 #define VM_MAX_READAHEAD 128 /* kbytes */
1077 #define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */
1078 #define VM_MAX_CACHE_HIT 256 /* max pages in a row in cache before
1079 * turning readahead off */
1081 int do_page_cache_readahead(struct address_space
*mapping
, struct file
*filp
,
1082 pgoff_t offset
, unsigned long nr_to_read
);
1083 int force_page_cache_readahead(struct address_space
*mapping
, struct file
*filp
,
1084 pgoff_t offset
, unsigned long nr_to_read
);
1085 unsigned long page_cache_readahead(struct address_space
*mapping
,
1086 struct file_ra_state
*ra
,
1089 unsigned long size
);
1090 void handle_ra_miss(struct address_space
*mapping
,
1091 struct file_ra_state
*ra
, pgoff_t offset
);
1092 unsigned long max_sane_readahead(unsigned long nr
);
1094 /* Do stack extension */
1095 extern int expand_stack(struct vm_area_struct
*vma
, unsigned long address
);
1097 extern int expand_upwards(struct vm_area_struct
*vma
, unsigned long address
);
1100 /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */
1101 extern struct vm_area_struct
* find_vma(struct mm_struct
* mm
, unsigned long addr
);
1102 extern struct vm_area_struct
* find_vma_prev(struct mm_struct
* mm
, unsigned long addr
,
1103 struct vm_area_struct
**pprev
);
1105 /* Look up the first VMA which intersects the interval start_addr..end_addr-1,
1106 NULL if none. Assume start_addr < end_addr. */
1107 static inline struct vm_area_struct
* find_vma_intersection(struct mm_struct
* mm
, unsigned long start_addr
, unsigned long end_addr
)
1109 struct vm_area_struct
* vma
= find_vma(mm
,start_addr
);
1111 if (vma
&& end_addr
<= vma
->vm_start
)
1116 static inline unsigned long vma_pages(struct vm_area_struct
*vma
)
1118 return (vma
->vm_end
- vma
->vm_start
) >> PAGE_SHIFT
;
1121 pgprot_t
vm_get_page_prot(unsigned long vm_flags
);
1122 struct vm_area_struct
*find_extend_vma(struct mm_struct
*, unsigned long addr
);
1123 struct page
*vmalloc_to_page(void *addr
);
1124 unsigned long vmalloc_to_pfn(void *addr
);
1125 int remap_pfn_range(struct vm_area_struct
*, unsigned long addr
,
1126 unsigned long pfn
, unsigned long size
, pgprot_t
);
1127 int vm_insert_page(struct vm_area_struct
*, unsigned long addr
, struct page
*);
1128 int vm_insert_pfn(struct vm_area_struct
*vma
, unsigned long addr
,
1131 struct page
*follow_page(struct vm_area_struct
*, unsigned long address
,
1132 unsigned int foll_flags
);
1133 #define FOLL_WRITE 0x01 /* check pte is writable */
1134 #define FOLL_TOUCH 0x02 /* mark page accessed */
1135 #define FOLL_GET 0x04 /* do get_page on page */
1136 #define FOLL_ANON 0x08 /* give ZERO_PAGE if no pgtable */
1138 #ifdef CONFIG_PROC_FS
1139 void vm_stat_account(struct mm_struct
*, unsigned long, struct file
*, long);
1141 static inline void vm_stat_account(struct mm_struct
*mm
,
1142 unsigned long flags
, struct file
*file
, long pages
)
1145 #endif /* CONFIG_PROC_FS */
1147 #ifndef CONFIG_DEBUG_PAGEALLOC
1149 kernel_map_pages(struct page
*page
, int numpages
, int enable
) {}
1152 extern struct vm_area_struct
*get_gate_vma(struct task_struct
*tsk
);
1153 #ifdef __HAVE_ARCH_GATE_AREA
1154 int in_gate_area_no_task(unsigned long addr
);
1155 int in_gate_area(struct task_struct
*task
, unsigned long addr
);
1157 int in_gate_area_no_task(unsigned long addr
);
1158 #define in_gate_area(task, addr) ({(void)task; in_gate_area_no_task(addr);})
1159 #endif /* __HAVE_ARCH_GATE_AREA */
1161 int drop_caches_sysctl_handler(struct ctl_table
*, int, struct file
*,
1162 void __user
*, size_t *, loff_t
*);
1163 unsigned long shrink_slab(unsigned long scanned
, gfp_t gfp_mask
,
1164 unsigned long lru_pages
);
1165 void drop_pagecache(void);
1166 void drop_slab(void);
1169 #define randomize_va_space 0
1171 extern int randomize_va_space
;
1174 __attribute__((weak
)) const char *arch_vma_name(struct vm_area_struct
*vma
);
1176 #endif /* __KERNEL__ */
1177 #endif /* _LINUX_MM_H */