4 #include <linux/errno.h>
10 #include <linux/list.h>
11 #include <linux/mmzone.h>
12 #include <linux/rbtree.h>
13 #include <linux/atomic.h>
14 #include <linux/debug_locks.h>
15 #include <linux/mm_types.h>
16 #include <linux/range.h>
17 #include <linux/pfn.h>
18 #include <linux/bit_spinlock.h>
19 #include <linux/shrinker.h>
23 struct anon_vma_chain;
26 struct writeback_control;
28 #ifndef CONFIG_DISCONTIGMEM /* Don't use mapnrs, do it properly */
29 extern unsigned long max_mapnr;
32 extern unsigned long num_physpages;
33 extern unsigned long totalram_pages;
34 extern void * high_memory;
35 extern int page_cluster;
38 extern int sysctl_legacy_va_layout;
40 #define sysctl_legacy_va_layout 0
44 #include <asm/pgtable.h>
45 #include <asm/processor.h>
47 extern unsigned long sysctl_user_reserve_kbytes;
48 extern unsigned long sysctl_admin_reserve_kbytes;
50 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
52 /* to align the pointer to the (next) page boundary */
53 #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
55 /* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
56 #define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)addr, PAGE_SIZE)
59 * Linux kernel virtual memory manager primitives.
60 * The idea being to have a "virtual" mm in the same way
61 * we have a virtual fs - giving a cleaner interface to the
62 * mm details, and allowing different kinds of memory mappings
63 * (from shared memory to executable loading to arbitrary
67 extern struct kmem_cache *vm_area_cachep;
70 extern struct rb_root nommu_region_tree;
71 extern struct rw_semaphore nommu_region_sem;
73 extern unsigned int kobjsize(const void *objp);
77 * vm_flags in vm_area_struct, see mm_types.h.
79 #define VM_NONE 0x00000000
81 #define VM_READ 0x00000001 /* currently active flags */
82 #define VM_WRITE 0x00000002
83 #define VM_EXEC 0x00000004
84 #define VM_SHARED 0x00000008
86 /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */
87 #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */
88 #define VM_MAYWRITE 0x00000020
89 #define VM_MAYEXEC 0x00000040
90 #define VM_MAYSHARE 0x00000080
92 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */
93 #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */
94 #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */
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_ACCOUNT 0x00100000 /* Is a VM accounted object */
106 #define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */
107 #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */
108 #define VM_NONLINEAR 0x00800000 /* Is non-linear (remap_file_pages) */
109 #define VM_ARCH_1 0x01000000 /* Architecture-specific flag */
110 #define VM_DONTDUMP 0x04000000 /* Do not include in the core dump */
112 #define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */
113 #define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */
114 #define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */
115 #define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */
117 #if defined(CONFIG_X86)
118 # define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */
119 #elif defined(CONFIG_PPC)
120 # define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */
121 #elif defined(CONFIG_PARISC)
122 # define VM_GROWSUP VM_ARCH_1
123 #elif defined(CONFIG_METAG)
124 # define VM_GROWSUP VM_ARCH_1
125 #elif defined(CONFIG_IA64)
126 # define VM_GROWSUP VM_ARCH_1
127 #elif !defined(CONFIG_MMU)
128 # define VM_MAPPED_COPY VM_ARCH_1 /* T if mapped copy of data (nommu mmap) */
132 # define VM_GROWSUP VM_NONE
135 /* Bits set in the VMA until the stack is in its final location */
136 #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ)
138 #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */
139 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
142 #ifdef CONFIG_STACK_GROWSUP
143 #define VM_STACK_FLAGS (VM_GROWSUP | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
145 #define VM_STACK_FLAGS (VM_GROWSDOWN | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
148 #define VM_READHINTMASK (VM_SEQ_READ | VM_RAND_READ)
149 #define VM_ClearReadHint(v) (v)->vm_flags &= ~VM_READHINTMASK
150 #define VM_NormalReadHint(v) (!((v)->vm_flags & VM_READHINTMASK))
151 #define VM_SequentialReadHint(v) ((v)->vm_flags & VM_SEQ_READ)
152 #define VM_RandomReadHint(v) ((v)->vm_flags & VM_RAND_READ)
155 * Special vmas that are non-mergable, non-mlock()able.
156 * Note: mm/huge_memory.c VM_NO_THP depends on this definition.
158 #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP)
161 * mapping from the currently active vm_flags protection bits (the
162 * low four bits) to a page protection mask..
164 extern pgprot_t protection_map[16];
166 #define FAULT_FLAG_WRITE 0x01 /* Fault was a write access */
167 #define FAULT_FLAG_NONLINEAR 0x02 /* Fault was via a nonlinear mapping */
168 #define FAULT_FLAG_MKWRITE 0x04 /* Fault was mkwrite of existing pte */
169 #define FAULT_FLAG_ALLOW_RETRY 0x08 /* Retry fault if blocking */
170 #define FAULT_FLAG_RETRY_NOWAIT 0x10 /* Don't drop mmap_sem and wait when retrying */
171 #define FAULT_FLAG_KILLABLE 0x20 /* The fault task is in SIGKILL killable region */
172 #define FAULT_FLAG_TRIED 0x40 /* second try */
175 * vm_fault is filled by the the pagefault handler and passed to the vma's
176 * ->fault function. The vma's ->fault is responsible for returning a bitmask
177 * of VM_FAULT_xxx flags that give details about how the fault was handled.
179 * pgoff should be used in favour of virtual_address, if possible. If pgoff
180 * is used, one may implement ->remap_pages to get nonlinear mapping support.
183 unsigned int flags; /* FAULT_FLAG_xxx flags */
184 pgoff_t pgoff; /* Logical page offset based on vma */
185 void __user *virtual_address; /* Faulting virtual address */
187 struct page *page; /* ->fault handlers should return a
188 * page here, unless VM_FAULT_NOPAGE
189 * is set (which is also implied by
195 * These are the virtual MM functions - opening of an area, closing and
196 * unmapping it (needed to keep files on disk up-to-date etc), pointer
197 * to the functions called when a no-page or a wp-page exception occurs.
199 struct vm_operations_struct {
200 void (*open)(struct vm_area_struct * area);
201 void (*close)(struct vm_area_struct * area);
202 int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf);
204 /* notification that a previously read-only page is about to become
205 * writable, if an error is returned it will cause a SIGBUS */
206 int (*page_mkwrite)(struct vm_area_struct *vma, struct vm_fault *vmf);
208 /* called by access_process_vm when get_user_pages() fails, typically
209 * for use by special VMAs that can switch between memory and hardware
211 int (*access)(struct vm_area_struct *vma, unsigned long addr,
212 void *buf, int len, int write);
215 * set_policy() op must add a reference to any non-NULL @new mempolicy
216 * to hold the policy upon return. Caller should pass NULL @new to
217 * remove a policy and fall back to surrounding context--i.e. do not
218 * install a MPOL_DEFAULT policy, nor the task or system default
221 int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
224 * get_policy() op must add reference [mpol_get()] to any policy at
225 * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure
226 * in mm/mempolicy.c will do this automatically.
227 * get_policy() must NOT add a ref if the policy at (vma,addr) is not
228 * marked as MPOL_SHARED. vma policies are protected by the mmap_sem.
229 * If no [shared/vma] mempolicy exists at the addr, get_policy() op
230 * must return NULL--i.e., do not "fallback" to task or system default
233 struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
235 int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from,
236 const nodemask_t *to, unsigned long flags);
238 /* called by sys_remap_file_pages() to populate non-linear mapping */
239 int (*remap_pages)(struct vm_area_struct *vma, unsigned long addr,
240 unsigned long size, pgoff_t pgoff);
246 #define page_private(page) ((page)->private)
247 #define set_page_private(page, v) ((page)->private = (v))
249 /* It's valid only if the page is free path or free_list */
250 static inline void set_freepage_migratetype(struct page *page, int migratetype)
252 page->index = migratetype;
255 /* It's valid only if the page is free path or free_list */
256 static inline int get_freepage_migratetype(struct page *page)
262 * FIXME: take this include out, include page-flags.h in
263 * files which need it (119 of them)
265 #include <linux/page-flags.h>
266 #include <linux/huge_mm.h>
269 * Methods to modify the page usage count.
271 * What counts for a page usage:
272 * - cache mapping (page->mapping)
273 * - private data (page->private)
274 * - page mapped in a task's page tables, each mapping
275 * is counted separately
277 * Also, many kernel routines increase the page count before a critical
278 * routine so they can be sure the page doesn't go away from under them.
282 * Drop a ref, return true if the refcount fell to zero (the page has no users)
284 static inline int put_page_testzero(struct page *page)
286 VM_BUG_ON(atomic_read(&page->_count) == 0);
287 return atomic_dec_and_test(&page->_count);
291 * Try to grab a ref unless the page has a refcount of zero, return false if
294 static inline int get_page_unless_zero(struct page *page)
296 return atomic_inc_not_zero(&page->_count);
299 extern int page_is_ram(unsigned long pfn);
301 /* Support for virtually mapped pages */
302 struct page *vmalloc_to_page(const void *addr);
303 unsigned long vmalloc_to_pfn(const void *addr);
306 * Determine if an address is within the vmalloc range
308 * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
309 * is no special casing required.
311 static inline int is_vmalloc_addr(const void *x)
314 unsigned long addr = (unsigned long)x;
316 return addr >= VMALLOC_START && addr < VMALLOC_END;
322 extern int is_vmalloc_or_module_addr(const void *x);
324 static inline int is_vmalloc_or_module_addr(const void *x)
330 static inline void compound_lock(struct page *page)
332 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
333 VM_BUG_ON(PageSlab(page));
334 bit_spin_lock(PG_compound_lock, &page->flags);
338 static inline void compound_unlock(struct page *page)
340 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
341 VM_BUG_ON(PageSlab(page));
342 bit_spin_unlock(PG_compound_lock, &page->flags);
346 static inline unsigned long compound_lock_irqsave(struct page *page)
348 unsigned long uninitialized_var(flags);
349 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
350 local_irq_save(flags);
356 static inline void compound_unlock_irqrestore(struct page *page,
359 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
360 compound_unlock(page);
361 local_irq_restore(flags);
365 static inline struct page *compound_head(struct page *page)
367 if (unlikely(PageTail(page))) {
368 struct page *head = page->first_page;
371 * page->first_page may be a dangling pointer to an old
372 * compound page, so recheck that it is still a tail
373 * page before returning.
376 if (likely(PageTail(page)))
383 * The atomic page->_mapcount, starts from -1: so that transitions
384 * both from it and to it can be tracked, using atomic_inc_and_test
385 * and atomic_add_negative(-1).
387 static inline void page_mapcount_reset(struct page *page)
389 atomic_set(&(page)->_mapcount, -1);
392 static inline int page_mapcount(struct page *page)
394 return atomic_read(&(page)->_mapcount) + 1;
397 static inline int page_count(struct page *page)
399 return atomic_read(&compound_head(page)->_count);
402 static inline void get_huge_page_tail(struct page *page)
405 * __split_huge_page_refcount() cannot run
408 VM_BUG_ON(page_mapcount(page) < 0);
409 VM_BUG_ON(atomic_read(&page->_count) != 0);
410 atomic_inc(&page->_mapcount);
413 extern bool __get_page_tail(struct page *page);
415 static inline void get_page(struct page *page)
417 if (unlikely(PageTail(page)))
418 if (likely(__get_page_tail(page)))
421 * Getting a normal page or the head of a compound page
422 * requires to already have an elevated page->_count.
424 VM_BUG_ON(atomic_read(&page->_count) <= 0);
425 atomic_inc(&page->_count);
428 static inline struct page *virt_to_head_page(const void *x)
430 struct page *page = virt_to_page(x);
431 return compound_head(page);
435 * Setup the page count before being freed into the page allocator for
436 * the first time (boot or memory hotplug)
438 static inline void init_page_count(struct page *page)
440 atomic_set(&page->_count, 1);
444 * PageBuddy() indicate that the page is free and in the buddy system
445 * (see mm/page_alloc.c).
447 * PAGE_BUDDY_MAPCOUNT_VALUE must be <= -2 but better not too close to
448 * -2 so that an underflow of the page_mapcount() won't be mistaken
449 * for a genuine PAGE_BUDDY_MAPCOUNT_VALUE. -128 can be created very
450 * efficiently by most CPU architectures.
452 #define PAGE_BUDDY_MAPCOUNT_VALUE (-128)
454 static inline int PageBuddy(struct page *page)
456 return atomic_read(&page->_mapcount) == PAGE_BUDDY_MAPCOUNT_VALUE;
459 static inline void __SetPageBuddy(struct page *page)
461 VM_BUG_ON(atomic_read(&page->_mapcount) != -1);
462 atomic_set(&page->_mapcount, PAGE_BUDDY_MAPCOUNT_VALUE);
465 static inline void __ClearPageBuddy(struct page *page)
467 VM_BUG_ON(!PageBuddy(page));
468 atomic_set(&page->_mapcount, -1);
471 void put_page(struct page *page);
472 void put_pages_list(struct list_head *pages);
474 void split_page(struct page *page, unsigned int order);
475 int split_free_page(struct page *page);
478 * Compound pages have a destructor function. Provide a
479 * prototype for that function and accessor functions.
480 * These are _only_ valid on the head of a PG_compound page.
482 typedef void compound_page_dtor(struct page *);
484 static inline void set_compound_page_dtor(struct page *page,
485 compound_page_dtor *dtor)
487 page[1].lru.next = (void *)dtor;
490 static inline compound_page_dtor *get_compound_page_dtor(struct page *page)
492 return (compound_page_dtor *)page[1].lru.next;
495 static inline int compound_order(struct page *page)
499 return (unsigned long)page[1].lru.prev;
502 static inline int compound_trans_order(struct page *page)
510 flags = compound_lock_irqsave(page);
511 order = compound_order(page);
512 compound_unlock_irqrestore(page, flags);
516 static inline void set_compound_order(struct page *page, unsigned long order)
518 page[1].lru.prev = (void *)order;
523 * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when
524 * servicing faults for write access. In the normal case, do always want
525 * pte_mkwrite. But get_user_pages can cause write faults for mappings
526 * that do not have writing enabled, when used by access_process_vm.
528 static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
530 if (likely(vma->vm_flags & VM_WRITE))
531 pte = pte_mkwrite(pte);
537 * Multiple processes may "see" the same page. E.g. for untouched
538 * mappings of /dev/null, all processes see the same page full of
539 * zeroes, and text pages of executables and shared libraries have
540 * only one copy in memory, at most, normally.
542 * For the non-reserved pages, page_count(page) denotes a reference count.
543 * page_count() == 0 means the page is free. page->lru is then used for
544 * freelist management in the buddy allocator.
545 * page_count() > 0 means the page has been allocated.
547 * Pages are allocated by the slab allocator in order to provide memory
548 * to kmalloc and kmem_cache_alloc. In this case, the management of the
549 * page, and the fields in 'struct page' are the responsibility of mm/slab.c
550 * unless a particular usage is carefully commented. (the responsibility of
551 * freeing the kmalloc memory is the caller's, of course).
553 * A page may be used by anyone else who does a __get_free_page().
554 * In this case, page_count still tracks the references, and should only
555 * be used through the normal accessor functions. The top bits of page->flags
556 * and page->virtual store page management information, but all other fields
557 * are unused and could be used privately, carefully. The management of this
558 * page is the responsibility of the one who allocated it, and those who have
559 * subsequently been given references to it.
561 * The other pages (we may call them "pagecache pages") are completely
562 * managed by the Linux memory manager: I/O, buffers, swapping etc.
563 * The following discussion applies only to them.
565 * A pagecache page contains an opaque `private' member, which belongs to the
566 * page's address_space. Usually, this is the address of a circular list of
567 * the page's disk buffers. PG_private must be set to tell the VM to call
568 * into the filesystem to release these pages.
570 * A page may belong to an inode's memory mapping. In this case, page->mapping
571 * is the pointer to the inode, and page->index is the file offset of the page,
572 * in units of PAGE_CACHE_SIZE.
574 * If pagecache pages are not associated with an inode, they are said to be
575 * anonymous pages. These may become associated with the swapcache, and in that
576 * case PG_swapcache is set, and page->private is an offset into the swapcache.
578 * In either case (swapcache or inode backed), the pagecache itself holds one
579 * reference to the page. Setting PG_private should also increment the
580 * refcount. The each user mapping also has a reference to the page.
582 * The pagecache pages are stored in a per-mapping radix tree, which is
583 * rooted at mapping->page_tree, and indexed by offset.
584 * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space
585 * lists, we instead now tag pages as dirty/writeback in the radix tree.
587 * All pagecache pages may be subject to I/O:
588 * - inode pages may need to be read from disk,
589 * - inode pages which have been modified and are MAP_SHARED may need
590 * to be written back to the inode on disk,
591 * - anonymous pages (including MAP_PRIVATE file mappings) which have been
592 * modified may need to be swapped out to swap space and (later) to be read
597 * The zone field is never updated after free_area_init_core()
598 * sets it, so none of the operations on it need to be atomic.
601 /* Page flags: | [SECTION] | [NODE] | ZONE | [LAST_NID] | ... | FLAGS | */
602 #define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH)
603 #define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH)
604 #define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH)
605 #define LAST_NID_PGOFF (ZONES_PGOFF - LAST_NID_WIDTH)
608 * Define the bit shifts to access each section. For non-existent
609 * sections we define the shift as 0; that plus a 0 mask ensures
610 * the compiler will optimise away reference to them.
612 #define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0))
613 #define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0))
614 #define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0))
615 #define LAST_NID_PGSHIFT (LAST_NID_PGOFF * (LAST_NID_WIDTH != 0))
617 /* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allocator */
618 #ifdef NODE_NOT_IN_PAGE_FLAGS
619 #define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT)
620 #define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF)? \
621 SECTIONS_PGOFF : ZONES_PGOFF)
623 #define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT)
624 #define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF)? \
625 NODES_PGOFF : ZONES_PGOFF)
628 #define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0))
630 #if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
631 #error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
634 #define ZONES_MASK ((1UL << ZONES_WIDTH) - 1)
635 #define NODES_MASK ((1UL << NODES_WIDTH) - 1)
636 #define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1)
637 #define LAST_NID_MASK ((1UL << LAST_NID_WIDTH) - 1)
638 #define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1)
640 static inline enum zone_type page_zonenum(const struct page *page)
642 return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK;
645 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
646 #define SECTION_IN_PAGE_FLAGS
650 * The identification function is only used by the buddy allocator for
651 * determining if two pages could be buddies. We are not really
652 * identifying a zone since we could be using a the section number
653 * id if we have not node id available in page flags.
654 * We guarantee only that it will return the same value for two
655 * combinable pages in a zone.
657 static inline int page_zone_id(struct page *page)
659 return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK;
662 static inline int zone_to_nid(struct zone *zone)
671 #ifdef NODE_NOT_IN_PAGE_FLAGS
672 extern int page_to_nid(const struct page *page);
674 static inline int page_to_nid(const struct page *page)
676 return (page->flags >> NODES_PGSHIFT) & NODES_MASK;
680 #ifdef CONFIG_NUMA_BALANCING
681 #ifdef LAST_NID_NOT_IN_PAGE_FLAGS
682 static inline int page_nid_xchg_last(struct page *page, int nid)
684 return xchg(&page->_last_nid, nid);
687 static inline int page_nid_last(struct page *page)
689 return page->_last_nid;
691 static inline void page_nid_reset_last(struct page *page)
693 page->_last_nid = -1;
696 static inline int page_nid_last(struct page *page)
698 return (page->flags >> LAST_NID_PGSHIFT) & LAST_NID_MASK;
701 extern int page_nid_xchg_last(struct page *page, int nid);
703 static inline void page_nid_reset_last(struct page *page)
705 int nid = (1 << LAST_NID_SHIFT) - 1;
707 page->flags &= ~(LAST_NID_MASK << LAST_NID_PGSHIFT);
708 page->flags |= (nid & LAST_NID_MASK) << LAST_NID_PGSHIFT;
710 #endif /* LAST_NID_NOT_IN_PAGE_FLAGS */
712 static inline int page_nid_xchg_last(struct page *page, int nid)
714 return page_to_nid(page);
717 static inline int page_nid_last(struct page *page)
719 return page_to_nid(page);
722 static inline void page_nid_reset_last(struct page *page)
727 static inline struct zone *page_zone(const struct page *page)
729 return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
732 #ifdef SECTION_IN_PAGE_FLAGS
733 static inline void set_page_section(struct page *page, unsigned long section)
735 page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT);
736 page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT;
739 static inline unsigned long page_to_section(const struct page *page)
741 return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
745 static inline void set_page_zone(struct page *page, enum zone_type zone)
747 page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
748 page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
751 static inline void set_page_node(struct page *page, unsigned long node)
753 page->flags &= ~(NODES_MASK << NODES_PGSHIFT);
754 page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
757 static inline void set_page_links(struct page *page, enum zone_type zone,
758 unsigned long node, unsigned long pfn)
760 set_page_zone(page, zone);
761 set_page_node(page, node);
762 #ifdef SECTION_IN_PAGE_FLAGS
763 set_page_section(page, pfn_to_section_nr(pfn));
768 * Some inline functions in vmstat.h depend on page_zone()
770 #include <linux/vmstat.h>
772 static __always_inline void *lowmem_page_address(const struct page *page)
774 return __va(PFN_PHYS(page_to_pfn(page)));
777 #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
778 #define HASHED_PAGE_VIRTUAL
781 #if defined(WANT_PAGE_VIRTUAL)
782 static inline void *page_address(const struct page *page)
784 return page->virtual;
786 static inline void set_page_address(struct page *page, void *address)
788 page->virtual = address;
790 #define page_address_init() do { } while(0)
793 #if defined(HASHED_PAGE_VIRTUAL)
794 void *page_address(const struct page *page);
795 void set_page_address(struct page *page, void *virtual);
796 void page_address_init(void);
799 #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
800 #define page_address(page) lowmem_page_address(page)
801 #define set_page_address(page, address) do { } while(0)
802 #define page_address_init() do { } while(0)
806 * On an anonymous page mapped into a user virtual memory area,
807 * page->mapping points to its anon_vma, not to a struct address_space;
808 * with the PAGE_MAPPING_ANON bit set to distinguish it. See rmap.h.
810 * On an anonymous page in a VM_MERGEABLE area, if CONFIG_KSM is enabled,
811 * the PAGE_MAPPING_KSM bit may be set along with the PAGE_MAPPING_ANON bit;
812 * and then page->mapping points, not to an anon_vma, but to a private
813 * structure which KSM associates with that merged page. See ksm.h.
815 * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is currently never used.
817 * Please note that, confusingly, "page_mapping" refers to the inode
818 * address_space which maps the page from disk; whereas "page_mapped"
819 * refers to user virtual address space into which the page is mapped.
821 #define PAGE_MAPPING_ANON 1
822 #define PAGE_MAPPING_KSM 2
823 #define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_KSM)
825 extern struct address_space *page_mapping(struct page *page);
827 /* Neutral page->mapping pointer to address_space or anon_vma or other */
828 static inline void *page_rmapping(struct page *page)
830 return (void *)((unsigned long)page->mapping & ~PAGE_MAPPING_FLAGS);
833 extern struct address_space *__page_file_mapping(struct page *);
836 struct address_space *page_file_mapping(struct page *page)
838 if (unlikely(PageSwapCache(page)))
839 return __page_file_mapping(page);
841 return page->mapping;
844 static inline int PageAnon(struct page *page)
846 return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0;
850 * Return the pagecache index of the passed page. Regular pagecache pages
851 * use ->index whereas swapcache pages use ->private
853 static inline pgoff_t page_index(struct page *page)
855 if (unlikely(PageSwapCache(page)))
856 return page_private(page);
860 extern pgoff_t __page_file_index(struct page *page);
863 * Return the file index of the page. Regular pagecache pages use ->index
864 * whereas swapcache pages use swp_offset(->private)
866 static inline pgoff_t page_file_index(struct page *page)
868 if (unlikely(PageSwapCache(page)))
869 return __page_file_index(page);
875 * Return true if this page is mapped into pagetables.
877 static inline int page_mapped(struct page *page)
879 return atomic_read(&(page)->_mapcount) >= 0;
883 * Different kinds of faults, as returned by handle_mm_fault().
884 * Used to decide whether a process gets delivered SIGBUS or
885 * just gets major/minor fault counters bumped up.
888 #define VM_FAULT_MINOR 0 /* For backwards compat. Remove me quickly. */
890 #define VM_FAULT_OOM 0x0001
891 #define VM_FAULT_SIGBUS 0x0002
892 #define VM_FAULT_MAJOR 0x0004
893 #define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
894 #define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
895 #define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index encoded in upper bits */
897 #define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */
898 #define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */
899 #define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
901 #define VM_FAULT_HWPOISON_LARGE_MASK 0xf000 /* encodes hpage index for large hwpoison */
903 #define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_HWPOISON | \
904 VM_FAULT_HWPOISON_LARGE)
906 /* Encode hstate index for a hwpoisoned large page */
907 #define VM_FAULT_SET_HINDEX(x) ((x) << 12)
908 #define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
911 * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
913 extern void pagefault_out_of_memory(void);
915 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
918 * Flags passed to show_mem() and show_free_areas() to suppress output in
921 #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */
922 #define SHOW_MEM_FILTER_PAGE_COUNT (0x0002u) /* page type count */
924 extern void show_free_areas(unsigned int flags);
925 extern bool skip_free_areas_node(unsigned int flags, int nid);
927 int shmem_zero_setup(struct vm_area_struct *);
929 extern int can_do_mlock(void);
930 extern int user_shm_lock(size_t, struct user_struct *);
931 extern void user_shm_unlock(size_t, struct user_struct *);
934 * Parameter block passed down to zap_pte_range in exceptional cases.
937 struct vm_area_struct *nonlinear_vma; /* Check page->index if set */
938 struct address_space *check_mapping; /* Check page->mapping if set */
939 pgoff_t first_index; /* Lowest page->index to unmap */
940 pgoff_t last_index; /* Highest page->index to unmap */
943 struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
946 int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
948 void zap_page_range(struct vm_area_struct *vma, unsigned long address,
949 unsigned long size, struct zap_details *);
950 void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
951 unsigned long start, unsigned long end);
954 * mm_walk - callbacks for walk_page_range
955 * @pgd_entry: if set, called for each non-empty PGD (top-level) entry
956 * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry
957 * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
958 * this handler is required to be able to handle
959 * pmd_trans_huge() pmds. They may simply choose to
960 * split_huge_page() instead of handling it explicitly.
961 * @pte_entry: if set, called for each non-empty PTE (4th-level) entry
962 * @pte_hole: if set, called for each hole at all levels
963 * @hugetlb_entry: if set, called for each hugetlb entry
964 * *Caution*: The caller must hold mmap_sem() if @hugetlb_entry
967 * (see walk_page_range for more details)
970 int (*pgd_entry)(pgd_t *pgd, unsigned long addr,
971 unsigned long next, struct mm_walk *walk);
972 int (*pud_entry)(pud_t *pud, unsigned long addr,
973 unsigned long next, struct mm_walk *walk);
974 int (*pmd_entry)(pmd_t *pmd, unsigned long addr,
975 unsigned long next, struct mm_walk *walk);
976 int (*pte_entry)(pte_t *pte, unsigned long addr,
977 unsigned long next, struct mm_walk *walk);
978 int (*pte_hole)(unsigned long addr, unsigned long next,
979 struct mm_walk *walk);
980 int (*hugetlb_entry)(pte_t *pte, unsigned long hmask,
981 unsigned long addr, unsigned long next,
982 struct mm_walk *walk);
983 struct mm_struct *mm;
987 int walk_page_range(unsigned long addr, unsigned long end,
988 struct mm_walk *walk);
989 void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
990 unsigned long end, unsigned long floor, unsigned long ceiling);
991 int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
992 struct vm_area_struct *vma);
993 void unmap_mapping_range(struct address_space *mapping,
994 loff_t const holebegin, loff_t const holelen, int even_cows);
995 int follow_pfn(struct vm_area_struct *vma, unsigned long address,
997 int follow_phys(struct vm_area_struct *vma, unsigned long address,
998 unsigned int flags, unsigned long *prot, resource_size_t *phys);
999 int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
1000 void *buf, int len, int write);
1002 static inline void unmap_shared_mapping_range(struct address_space *mapping,
1003 loff_t const holebegin, loff_t const holelen)
1005 unmap_mapping_range(mapping, holebegin, holelen, 0);
1008 extern void truncate_pagecache(struct inode *inode, loff_t old, loff_t new);
1009 extern void truncate_setsize(struct inode *inode, loff_t newsize);
1010 void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);
1011 void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);
1012 int truncate_inode_page(struct address_space *mapping, struct page *page);
1013 int generic_error_remove_page(struct address_space *mapping, struct page *page);
1014 int invalidate_inode_page(struct page *page);
1017 extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
1018 unsigned long address, unsigned int flags);
1019 extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
1020 unsigned long address, unsigned int fault_flags);
1022 static inline int handle_mm_fault(struct mm_struct *mm,
1023 struct vm_area_struct *vma, unsigned long address,
1026 /* should never happen if there's no MMU */
1028 return VM_FAULT_SIGBUS;
1030 static inline int fixup_user_fault(struct task_struct *tsk,
1031 struct mm_struct *mm, unsigned long address,
1032 unsigned int fault_flags)
1034 /* should never happen if there's no MMU */
1040 extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write);
1041 extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
1042 void *buf, int len, int write);
1044 long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
1045 unsigned long start, unsigned long nr_pages,
1046 unsigned int foll_flags, struct page **pages,
1047 struct vm_area_struct **vmas, int *nonblocking);
1048 long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
1049 unsigned long start, unsigned long nr_pages,
1050 int write, int force, struct page **pages,
1051 struct vm_area_struct **vmas);
1052 int get_user_pages_fast(unsigned long start, int nr_pages, int write,
1053 struct page **pages);
1055 int get_kernel_pages(const struct kvec *iov, int nr_pages, int write,
1056 struct page **pages);
1057 int get_kernel_page(unsigned long start, int write, struct page **pages);
1058 struct page *get_dump_page(unsigned long addr);
1060 extern int try_to_release_page(struct page * page, gfp_t gfp_mask);
1061 extern void do_invalidatepage(struct page *page, unsigned long offset);
1063 int __set_page_dirty_nobuffers(struct page *page);
1064 int __set_page_dirty_no_writeback(struct page *page);
1065 int redirty_page_for_writepage(struct writeback_control *wbc,
1067 void account_page_dirtied(struct page *page, struct address_space *mapping);
1068 void account_page_writeback(struct page *page);
1069 int set_page_dirty(struct page *page);
1070 int set_page_dirty_lock(struct page *page);
1071 int clear_page_dirty_for_io(struct page *page);
1073 /* Is the vma a continuation of the stack vma above it? */
1074 static inline int vma_growsdown(struct vm_area_struct *vma, unsigned long addr)
1076 return vma && (vma->vm_end == addr) && (vma->vm_flags & VM_GROWSDOWN);
1079 static inline int stack_guard_page_start(struct vm_area_struct *vma,
1082 return (vma->vm_flags & VM_GROWSDOWN) &&
1083 (vma->vm_start == addr) &&
1084 !vma_growsdown(vma->vm_prev, addr);
1087 /* Is the vma a continuation of the stack vma below it? */
1088 static inline int vma_growsup(struct vm_area_struct *vma, unsigned long addr)
1090 return vma && (vma->vm_start == addr) && (vma->vm_flags & VM_GROWSUP);
1093 static inline int stack_guard_page_end(struct vm_area_struct *vma,
1096 return (vma->vm_flags & VM_GROWSUP) &&
1097 (vma->vm_end == addr) &&
1098 !vma_growsup(vma->vm_next, addr);
1102 vm_is_stack(struct task_struct *task, struct vm_area_struct *vma, int in_group);
1104 extern unsigned long move_page_tables(struct vm_area_struct *vma,
1105 unsigned long old_addr, struct vm_area_struct *new_vma,
1106 unsigned long new_addr, unsigned long len,
1107 bool need_rmap_locks);
1108 extern unsigned long change_protection(struct vm_area_struct *vma, unsigned long start,
1109 unsigned long end, pgprot_t newprot,
1110 int dirty_accountable, int prot_numa);
1111 extern int mprotect_fixup(struct vm_area_struct *vma,
1112 struct vm_area_struct **pprev, unsigned long start,
1113 unsigned long end, unsigned long newflags);
1116 * doesn't attempt to fault and will return short.
1118 int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
1119 struct page **pages);
1121 * per-process(per-mm_struct) statistics.
1123 static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
1125 long val = atomic_long_read(&mm->rss_stat.count[member]);
1127 #ifdef SPLIT_RSS_COUNTING
1129 * counter is updated in asynchronous manner and may go to minus.
1130 * But it's never be expected number for users.
1135 return (unsigned long)val;
1138 static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
1140 atomic_long_add(value, &mm->rss_stat.count[member]);
1143 static inline void inc_mm_counter(struct mm_struct *mm, int member)
1145 atomic_long_inc(&mm->rss_stat.count[member]);
1148 static inline void dec_mm_counter(struct mm_struct *mm, int member)
1150 atomic_long_dec(&mm->rss_stat.count[member]);
1153 static inline unsigned long get_mm_rss(struct mm_struct *mm)
1155 return get_mm_counter(mm, MM_FILEPAGES) +
1156 get_mm_counter(mm, MM_ANONPAGES);
1159 static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
1161 return max(mm->hiwater_rss, get_mm_rss(mm));
1164 static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
1166 return max(mm->hiwater_vm, mm->total_vm);
1169 static inline void update_hiwater_rss(struct mm_struct *mm)
1171 unsigned long _rss = get_mm_rss(mm);
1173 if ((mm)->hiwater_rss < _rss)
1174 (mm)->hiwater_rss = _rss;
1177 static inline void update_hiwater_vm(struct mm_struct *mm)
1179 if (mm->hiwater_vm < mm->total_vm)
1180 mm->hiwater_vm = mm->total_vm;
1183 static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
1184 struct mm_struct *mm)
1186 unsigned long hiwater_rss = get_mm_hiwater_rss(mm);
1188 if (*maxrss < hiwater_rss)
1189 *maxrss = hiwater_rss;
1192 #if defined(SPLIT_RSS_COUNTING)
1193 void sync_mm_rss(struct mm_struct *mm);
1195 static inline void sync_mm_rss(struct mm_struct *mm)
1200 int vma_wants_writenotify(struct vm_area_struct *vma);
1202 extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
1204 static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
1208 __cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl));
1212 #ifdef __PAGETABLE_PUD_FOLDED
1213 static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd,
1214 unsigned long address)
1219 int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
1222 #ifdef __PAGETABLE_PMD_FOLDED
1223 static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
1224 unsigned long address)
1229 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);
1232 int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
1233 pmd_t *pmd, unsigned long address);
1234 int __pte_alloc_kernel(pmd_t *pmd, unsigned long address);
1237 * The following ifdef needed to get the 4level-fixup.h header to work.
1238 * Remove it when 4level-fixup.h has been removed.
1240 #if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK)
1241 static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
1243 return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))?
1244 NULL: pud_offset(pgd, address);
1247 static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
1249 return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
1250 NULL: pmd_offset(pud, address);
1252 #endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */
1254 #if USE_SPLIT_PTLOCKS
1256 * We tuck a spinlock to guard each pagetable page into its struct page,
1257 * at page->private, with BUILD_BUG_ON to make sure that this will not
1258 * overflow into the next struct page (as it might with DEBUG_SPINLOCK).
1259 * When freeing, reset page->mapping so free_pages_check won't complain.
1261 #define __pte_lockptr(page) &((page)->ptl)
1262 #define pte_lock_init(_page) do { \
1263 spin_lock_init(__pte_lockptr(_page)); \
1265 #define pte_lock_deinit(page) ((page)->mapping = NULL)
1266 #define pte_lockptr(mm, pmd) ({(void)(mm); __pte_lockptr(pmd_page(*(pmd)));})
1267 #else /* !USE_SPLIT_PTLOCKS */
1269 * We use mm->page_table_lock to guard all pagetable pages of the mm.
1271 #define pte_lock_init(page) do {} while (0)
1272 #define pte_lock_deinit(page) do {} while (0)
1273 #define pte_lockptr(mm, pmd) ({(void)(pmd); &(mm)->page_table_lock;})
1274 #endif /* USE_SPLIT_PTLOCKS */
1276 static inline void pgtable_page_ctor(struct page *page)
1278 pte_lock_init(page);
1279 inc_zone_page_state(page, NR_PAGETABLE);
1282 static inline void pgtable_page_dtor(struct page *page)
1284 pte_lock_deinit(page);
1285 dec_zone_page_state(page, NR_PAGETABLE);
1288 #define pte_offset_map_lock(mm, pmd, address, ptlp) \
1290 spinlock_t *__ptl = pte_lockptr(mm, pmd); \
1291 pte_t *__pte = pte_offset_map(pmd, address); \
1297 #define pte_unmap_unlock(pte, ptl) do { \
1302 #define pte_alloc_map(mm, vma, pmd, address) \
1303 ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, vma, \
1305 NULL: pte_offset_map(pmd, address))
1307 #define pte_alloc_map_lock(mm, pmd, address, ptlp) \
1308 ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, NULL, \
1310 NULL: pte_offset_map_lock(mm, pmd, address, ptlp))
1312 #define pte_alloc_kernel(pmd, address) \
1313 ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd, address))? \
1314 NULL: pte_offset_kernel(pmd, address))
1316 extern void free_area_init(unsigned long * zones_size);
1317 extern void free_area_init_node(int nid, unsigned long * zones_size,
1318 unsigned long zone_start_pfn, unsigned long *zholes_size);
1319 extern void free_initmem(void);
1322 * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
1323 * into the buddy system. The freed pages will be poisoned with pattern
1324 * "poison" if it's non-zero.
1325 * Return pages freed into the buddy system.
1327 extern unsigned long free_reserved_area(unsigned long start, unsigned long end,
1328 int poison, char *s);
1329 #ifdef CONFIG_HIGHMEM
1331 * Free a highmem page into the buddy system, adjusting totalhigh_pages
1332 * and totalram_pages.
1334 extern void free_highmem_page(struct page *page);
1337 static inline void adjust_managed_page_count(struct page *page, long count)
1339 totalram_pages += count;
1342 /* Free the reserved page into the buddy system, so it gets managed. */
1343 static inline void __free_reserved_page(struct page *page)
1345 ClearPageReserved(page);
1346 init_page_count(page);
1350 static inline void free_reserved_page(struct page *page)
1352 __free_reserved_page(page);
1353 adjust_managed_page_count(page, 1);
1356 static inline void mark_page_reserved(struct page *page)
1358 SetPageReserved(page);
1359 adjust_managed_page_count(page, -1);
1363 * Default method to free all the __init memory into the buddy system.
1364 * The freed pages will be poisoned with pattern "poison" if it is
1365 * non-zero. Return pages freed into the buddy system.
1367 static inline unsigned long free_initmem_default(int poison)
1369 extern char __init_begin[], __init_end[];
1371 return free_reserved_area(PAGE_ALIGN((unsigned long)&__init_begin) ,
1372 ((unsigned long)&__init_end) & PAGE_MASK,
1373 poison, "unused kernel");
1376 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
1378 * With CONFIG_HAVE_MEMBLOCK_NODE_MAP set, an architecture may initialise its
1379 * zones, allocate the backing mem_map and account for memory holes in a more
1380 * architecture independent manner. This is a substitute for creating the
1381 * zone_sizes[] and zholes_size[] arrays and passing them to
1382 * free_area_init_node()
1384 * An architecture is expected to register range of page frames backed by
1385 * physical memory with memblock_add[_node]() before calling
1386 * free_area_init_nodes() passing in the PFN each zone ends at. At a basic
1387 * usage, an architecture is expected to do something like
1389 * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn,
1391 * for_each_valid_physical_page_range()
1392 * memblock_add_node(base, size, nid)
1393 * free_area_init_nodes(max_zone_pfns);
1395 * free_bootmem_with_active_regions() calls free_bootmem_node() for each
1396 * registered physical page range. Similarly
1397 * sparse_memory_present_with_active_regions() calls memory_present() for
1398 * each range when SPARSEMEM is enabled.
1400 * See mm/page_alloc.c for more information on each function exposed by
1401 * CONFIG_HAVE_MEMBLOCK_NODE_MAP.
1403 extern void free_area_init_nodes(unsigned long *max_zone_pfn);
1404 unsigned long node_map_pfn_alignment(void);
1405 unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn,
1406 unsigned long end_pfn);
1407 extern unsigned long absent_pages_in_range(unsigned long start_pfn,
1408 unsigned long end_pfn);
1409 extern void get_pfn_range_for_nid(unsigned int nid,
1410 unsigned long *start_pfn, unsigned long *end_pfn);
1411 extern unsigned long find_min_pfn_with_active_regions(void);
1412 extern void free_bootmem_with_active_regions(int nid,
1413 unsigned long max_low_pfn);
1414 extern void sparse_memory_present_with_active_regions(int nid);
1416 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
1418 #if !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) && \
1419 !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID)
1420 static inline int __early_pfn_to_nid(unsigned long pfn)
1425 /* please see mm/page_alloc.c */
1426 extern int __meminit early_pfn_to_nid(unsigned long pfn);
1427 #ifdef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
1428 /* there is a per-arch backend function. */
1429 extern int __meminit __early_pfn_to_nid(unsigned long pfn);
1430 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
1433 extern void set_dma_reserve(unsigned long new_dma_reserve);
1434 extern void memmap_init_zone(unsigned long, int, unsigned long,
1435 unsigned long, enum memmap_context);
1436 extern void setup_per_zone_wmarks(void);
1437 extern int __meminit init_per_zone_wmark_min(void);
1438 extern void mem_init(void);
1439 extern void __init mmap_init(void);
1440 extern void show_mem(unsigned int flags);
1441 extern void si_meminfo(struct sysinfo * val);
1442 extern void si_meminfo_node(struct sysinfo *val, int nid);
1444 extern __printf(3, 4)
1445 void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...);
1447 extern void setup_per_cpu_pageset(void);
1449 extern void zone_pcp_update(struct zone *zone);
1450 extern void zone_pcp_reset(struct zone *zone);
1453 extern int min_free_kbytes;
1456 extern atomic_long_t mmap_pages_allocated;
1457 extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
1459 /* interval_tree.c */
1460 void vma_interval_tree_insert(struct vm_area_struct *node,
1461 struct rb_root *root);
1462 void vma_interval_tree_insert_after(struct vm_area_struct *node,
1463 struct vm_area_struct *prev,
1464 struct rb_root *root);
1465 void vma_interval_tree_remove(struct vm_area_struct *node,
1466 struct rb_root *root);
1467 struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root *root,
1468 unsigned long start, unsigned long last);
1469 struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
1470 unsigned long start, unsigned long last);
1472 #define vma_interval_tree_foreach(vma, root, start, last) \
1473 for (vma = vma_interval_tree_iter_first(root, start, last); \
1474 vma; vma = vma_interval_tree_iter_next(vma, start, last))
1476 static inline void vma_nonlinear_insert(struct vm_area_struct *vma,
1477 struct list_head *list)
1479 list_add_tail(&vma->shared.nonlinear, list);
1482 void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
1483 struct rb_root *root);
1484 void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
1485 struct rb_root *root);
1486 struct anon_vma_chain *anon_vma_interval_tree_iter_first(
1487 struct rb_root *root, unsigned long start, unsigned long last);
1488 struct anon_vma_chain *anon_vma_interval_tree_iter_next(
1489 struct anon_vma_chain *node, unsigned long start, unsigned long last);
1490 #ifdef CONFIG_DEBUG_VM_RB
1491 void anon_vma_interval_tree_verify(struct anon_vma_chain *node);
1494 #define anon_vma_interval_tree_foreach(avc, root, start, last) \
1495 for (avc = anon_vma_interval_tree_iter_first(root, start, last); \
1496 avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))
1499 extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin);
1500 extern int vma_adjust(struct vm_area_struct *vma, unsigned long start,
1501 unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert);
1502 extern struct vm_area_struct *vma_merge(struct mm_struct *,
1503 struct vm_area_struct *prev, unsigned long addr, unsigned long end,
1504 unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t,
1505 struct mempolicy *);
1506 extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
1507 extern int split_vma(struct mm_struct *,
1508 struct vm_area_struct *, unsigned long addr, int new_below);
1509 extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
1510 extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *,
1511 struct rb_node **, struct rb_node *);
1512 extern void unlink_file_vma(struct vm_area_struct *);
1513 extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
1514 unsigned long addr, unsigned long len, pgoff_t pgoff,
1515 bool *need_rmap_locks);
1516 extern void exit_mmap(struct mm_struct *);
1518 extern int mm_take_all_locks(struct mm_struct *mm);
1519 extern void mm_drop_all_locks(struct mm_struct *mm);
1521 extern void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
1522 extern struct file *get_mm_exe_file(struct mm_struct *mm);
1524 extern int may_expand_vm(struct mm_struct *mm, unsigned long npages);
1525 extern int install_special_mapping(struct mm_struct *mm,
1526 unsigned long addr, unsigned long len,
1527 unsigned long flags, struct page **pages);
1529 extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1531 extern unsigned long mmap_region(struct file *file, unsigned long addr,
1532 unsigned long len, vm_flags_t vm_flags, unsigned long pgoff);
1533 extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
1534 unsigned long len, unsigned long prot, unsigned long flags,
1535 unsigned long pgoff, unsigned long *populate);
1536 extern int do_munmap(struct mm_struct *, unsigned long, size_t);
1539 extern int __mm_populate(unsigned long addr, unsigned long len,
1541 static inline void mm_populate(unsigned long addr, unsigned long len)
1544 (void) __mm_populate(addr, len, 1);
1547 static inline void mm_populate(unsigned long addr, unsigned long len) {}
1550 /* These take the mm semaphore themselves */
1551 extern unsigned long vm_brk(unsigned long, unsigned long);
1552 extern int vm_munmap(unsigned long, size_t);
1553 extern unsigned long vm_mmap(struct file *, unsigned long,
1554 unsigned long, unsigned long,
1555 unsigned long, unsigned long);
1557 struct vm_unmapped_area_info {
1558 #define VM_UNMAPPED_AREA_TOPDOWN 1
1559 unsigned long flags;
1560 unsigned long length;
1561 unsigned long low_limit;
1562 unsigned long high_limit;
1563 unsigned long align_mask;
1564 unsigned long align_offset;
1567 extern unsigned long unmapped_area(struct vm_unmapped_area_info *info);
1568 extern unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info);
1571 * Search for an unmapped address range.
1573 * We are looking for a range that:
1574 * - does not intersect with any VMA;
1575 * - is contained within the [low_limit, high_limit) interval;
1576 * - is at least the desired size.
1577 * - satisfies (begin_addr & align_mask) == (align_offset & align_mask)
1579 static inline unsigned long
1580 vm_unmapped_area(struct vm_unmapped_area_info *info)
1582 if (!(info->flags & VM_UNMAPPED_AREA_TOPDOWN))
1583 return unmapped_area(info);
1585 return unmapped_area_topdown(info);
1589 extern void truncate_inode_pages(struct address_space *, loff_t);
1590 extern void truncate_inode_pages_range(struct address_space *,
1591 loff_t lstart, loff_t lend);
1593 /* generic vm_area_ops exported for stackable file systems */
1594 extern int filemap_fault(struct vm_area_struct *, struct vm_fault *);
1595 extern int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1597 /* mm/page-writeback.c */
1598 int write_one_page(struct page *page, int wait);
1599 void task_dirty_inc(struct task_struct *tsk);
1602 #define VM_MAX_READAHEAD 128 /* kbytes */
1603 #define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */
1605 int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
1606 pgoff_t offset, unsigned long nr_to_read);
1608 void page_cache_sync_readahead(struct address_space *mapping,
1609 struct file_ra_state *ra,
1612 unsigned long size);
1614 void page_cache_async_readahead(struct address_space *mapping,
1615 struct file_ra_state *ra,
1619 unsigned long size);
1621 unsigned long max_sane_readahead(unsigned long nr);
1622 unsigned long ra_submit(struct file_ra_state *ra,
1623 struct address_space *mapping,
1626 /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
1627 extern int expand_stack(struct vm_area_struct *vma, unsigned long address);
1629 /* CONFIG_STACK_GROWSUP still needs to to grow downwards at some places */
1630 extern int expand_downwards(struct vm_area_struct *vma,
1631 unsigned long address);
1633 extern int expand_upwards(struct vm_area_struct *vma, unsigned long address);
1635 #define expand_upwards(vma, address) do { } while (0)
1638 /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */
1639 extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr);
1640 extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
1641 struct vm_area_struct **pprev);
1643 /* Look up the first VMA which intersects the interval start_addr..end_addr-1,
1644 NULL if none. Assume start_addr < end_addr. */
1645 static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr)
1647 struct vm_area_struct * vma = find_vma(mm,start_addr);
1649 if (vma && end_addr <= vma->vm_start)
1654 static inline unsigned long vma_pages(struct vm_area_struct *vma)
1656 return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
1659 /* Look up the first VMA which exactly match the interval vm_start ... vm_end */
1660 static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
1661 unsigned long vm_start, unsigned long vm_end)
1663 struct vm_area_struct *vma = find_vma(mm, vm_start);
1665 if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
1672 pgprot_t vm_get_page_prot(unsigned long vm_flags);
1674 static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
1680 #ifdef CONFIG_ARCH_USES_NUMA_PROT_NONE
1681 unsigned long change_prot_numa(struct vm_area_struct *vma,
1682 unsigned long start, unsigned long end);
1685 struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr);
1686 int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
1687 unsigned long pfn, unsigned long size, pgprot_t);
1688 int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
1689 int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
1691 int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
1693 int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
1696 struct page *follow_page_mask(struct vm_area_struct *vma,
1697 unsigned long address, unsigned int foll_flags,
1698 unsigned int *page_mask);
1700 static inline struct page *follow_page(struct vm_area_struct *vma,
1701 unsigned long address, unsigned int foll_flags)
1703 unsigned int unused_page_mask;
1704 return follow_page_mask(vma, address, foll_flags, &unused_page_mask);
1707 #define FOLL_WRITE 0x01 /* check pte is writable */
1708 #define FOLL_TOUCH 0x02 /* mark page accessed */
1709 #define FOLL_GET 0x04 /* do get_page on page */
1710 #define FOLL_DUMP 0x08 /* give error on hole if it would be zero */
1711 #define FOLL_FORCE 0x10 /* get_user_pages read/write w/o permission */
1712 #define FOLL_NOWAIT 0x20 /* if a disk transfer is needed, start the IO
1713 * and return without waiting upon it */
1714 #define FOLL_MLOCK 0x40 /* mark page as mlocked */
1715 #define FOLL_SPLIT 0x80 /* don't return transhuge pages, split them */
1716 #define FOLL_HWPOISON 0x100 /* check page is hwpoisoned */
1717 #define FOLL_NUMA 0x200 /* force NUMA hinting page fault */
1718 #define FOLL_MIGRATION 0x400 /* wait for page to replace migration entry */
1720 typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr,
1722 extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
1723 unsigned long size, pte_fn_t fn, void *data);
1725 #ifdef CONFIG_PROC_FS
1726 void vm_stat_account(struct mm_struct *, unsigned long, struct file *, long);
1728 static inline void vm_stat_account(struct mm_struct *mm,
1729 unsigned long flags, struct file *file, long pages)
1731 mm->total_vm += pages;
1733 #endif /* CONFIG_PROC_FS */
1735 #ifdef CONFIG_DEBUG_PAGEALLOC
1736 extern void kernel_map_pages(struct page *page, int numpages, int enable);
1737 #ifdef CONFIG_HIBERNATION
1738 extern bool kernel_page_present(struct page *page);
1739 #endif /* CONFIG_HIBERNATION */
1742 kernel_map_pages(struct page *page, int numpages, int enable) {}
1743 #ifdef CONFIG_HIBERNATION
1744 static inline bool kernel_page_present(struct page *page) { return true; }
1745 #endif /* CONFIG_HIBERNATION */
1748 extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
1749 #ifdef __HAVE_ARCH_GATE_AREA
1750 int in_gate_area_no_mm(unsigned long addr);
1751 int in_gate_area(struct mm_struct *mm, unsigned long addr);
1753 int in_gate_area_no_mm(unsigned long addr);
1754 #define in_gate_area(mm, addr) ({(void)mm; in_gate_area_no_mm(addr);})
1755 #endif /* __HAVE_ARCH_GATE_AREA */
1757 #ifdef CONFIG_SYSCTL
1758 extern int sysctl_drop_caches;
1759 int drop_caches_sysctl_handler(struct ctl_table *, int,
1760 void __user *, size_t *, loff_t *);
1763 unsigned long shrink_slab(struct shrink_control *shrink,
1764 unsigned long nr_pages_scanned,
1765 unsigned long lru_pages);
1768 #define randomize_va_space 0
1770 extern int randomize_va_space;
1773 const char * arch_vma_name(struct vm_area_struct *vma);
1774 void print_vma_addr(char *prefix, unsigned long rip);
1776 void sparse_mem_maps_populate_node(struct page **map_map,
1777 unsigned long pnum_begin,
1778 unsigned long pnum_end,
1779 unsigned long map_count,
1782 struct page *sparse_mem_map_populate(unsigned long pnum, int nid);
1783 pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
1784 pud_t *vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node);
1785 pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
1786 pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node);
1787 void *vmemmap_alloc_block(unsigned long size, int node);
1788 void *vmemmap_alloc_block_buf(unsigned long size, int node);
1789 void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
1790 int vmemmap_populate_basepages(unsigned long start, unsigned long end,
1792 int vmemmap_populate(unsigned long start, unsigned long end, int node);
1793 void vmemmap_populate_print_last(void);
1794 #ifdef CONFIG_MEMORY_HOTPLUG
1795 void vmemmap_free(unsigned long start, unsigned long end);
1797 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
1798 unsigned long size);
1801 MF_COUNT_INCREASED = 1 << 0,
1802 MF_ACTION_REQUIRED = 1 << 1,
1803 MF_MUST_KILL = 1 << 2,
1805 extern int memory_failure(unsigned long pfn, int trapno, int flags);
1806 extern void memory_failure_queue(unsigned long pfn, int trapno, int flags);
1807 extern int unpoison_memory(unsigned long pfn);
1808 extern int sysctl_memory_failure_early_kill;
1809 extern int sysctl_memory_failure_recovery;
1810 extern void shake_page(struct page *p, int access);
1811 extern atomic_long_t num_poisoned_pages;
1812 extern int soft_offline_page(struct page *page, int flags);
1814 extern void dump_page(struct page *page);
1816 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS)
1817 extern void clear_huge_page(struct page *page,
1819 unsigned int pages_per_huge_page);
1820 extern void copy_user_huge_page(struct page *dst, struct page *src,
1821 unsigned long addr, struct vm_area_struct *vma,
1822 unsigned int pages_per_huge_page);
1823 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
1825 #ifdef CONFIG_DEBUG_PAGEALLOC
1826 extern unsigned int _debug_guardpage_minorder;
1828 static inline unsigned int debug_guardpage_minorder(void)
1830 return _debug_guardpage_minorder;
1833 static inline bool page_is_guard(struct page *page)
1835 return test_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags);
1838 static inline unsigned int debug_guardpage_minorder(void) { return 0; }
1839 static inline bool page_is_guard(struct page *page) { return false; }
1840 #endif /* CONFIG_DEBUG_PAGEALLOC */
1842 #if MAX_NUMNODES > 1
1843 void __init setup_nr_node_ids(void);
1845 static inline void setup_nr_node_ids(void) {}
1848 #endif /* __KERNEL__ */
1849 #endif /* _LINUX_MM_H */