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_NEED_MULTIPLE_NODES /* Don't use mapnrs, do it properly */
29 extern unsigned long max_mapnr;
31 static inline void set_max_mapnr(unsigned long limit)
36 static inline void set_max_mapnr(unsigned long limit) { }
39 extern unsigned long totalram_pages;
40 extern void * high_memory;
41 extern int page_cluster;
44 extern int sysctl_legacy_va_layout;
46 #define sysctl_legacy_va_layout 0
50 #include <asm/pgtable.h>
51 #include <asm/processor.h>
54 #define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0))
57 extern unsigned long sysctl_user_reserve_kbytes;
58 extern unsigned long sysctl_admin_reserve_kbytes;
60 extern int sysctl_overcommit_memory;
61 extern int sysctl_overcommit_ratio;
62 extern unsigned long sysctl_overcommit_kbytes;
64 extern int overcommit_ratio_handler(struct ctl_table *, int, void __user *,
66 extern int overcommit_kbytes_handler(struct ctl_table *, int, void __user *,
69 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
71 /* to align the pointer to the (next) page boundary */
72 #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
74 /* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
75 #define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)addr, PAGE_SIZE)
78 * Linux kernel virtual memory manager primitives.
79 * The idea being to have a "virtual" mm in the same way
80 * we have a virtual fs - giving a cleaner interface to the
81 * mm details, and allowing different kinds of memory mappings
82 * (from shared memory to executable loading to arbitrary
86 extern struct kmem_cache *vm_area_cachep;
89 extern struct rb_root nommu_region_tree;
90 extern struct rw_semaphore nommu_region_sem;
92 extern unsigned int kobjsize(const void *objp);
96 * vm_flags in vm_area_struct, see mm_types.h.
98 #define VM_NONE 0x00000000
100 #define VM_READ 0x00000001 /* currently active flags */
101 #define VM_WRITE 0x00000002
102 #define VM_EXEC 0x00000004
103 #define VM_SHARED 0x00000008
105 /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */
106 #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */
107 #define VM_MAYWRITE 0x00000020
108 #define VM_MAYEXEC 0x00000040
109 #define VM_MAYSHARE 0x00000080
111 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */
112 #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */
113 #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */
115 #define VM_LOCKED 0x00002000
116 #define VM_IO 0x00004000 /* Memory mapped I/O or similar */
118 /* Used by sys_madvise() */
119 #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */
120 #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */
122 #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */
123 #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */
124 #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */
125 #define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */
126 #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */
127 #define VM_NONLINEAR 0x00800000 /* Is non-linear (remap_file_pages) */
128 #define VM_ARCH_1 0x01000000 /* Architecture-specific flag */
129 #define VM_DONTDUMP 0x04000000 /* Do not include in the core dump */
131 #ifdef CONFIG_MEM_SOFT_DIRTY
132 # define VM_SOFTDIRTY 0x08000000 /* Not soft dirty clean area */
134 # define VM_SOFTDIRTY 0
137 #define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */
138 #define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */
139 #define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */
140 #define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */
142 #if defined(CONFIG_X86)
143 # define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */
144 #elif defined(CONFIG_PPC)
145 # define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */
146 #elif defined(CONFIG_PARISC)
147 # define VM_GROWSUP VM_ARCH_1
148 #elif defined(CONFIG_METAG)
149 # define VM_GROWSUP VM_ARCH_1
150 #elif defined(CONFIG_IA64)
151 # define VM_GROWSUP VM_ARCH_1
152 #elif !defined(CONFIG_MMU)
153 # define VM_MAPPED_COPY VM_ARCH_1 /* T if mapped copy of data (nommu mmap) */
157 # define VM_GROWSUP VM_NONE
160 /* Bits set in the VMA until the stack is in its final location */
161 #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ)
163 #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */
164 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
167 #ifdef CONFIG_STACK_GROWSUP
168 #define VM_STACK_FLAGS (VM_GROWSUP | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
170 #define VM_STACK_FLAGS (VM_GROWSDOWN | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
174 * Special vmas that are non-mergable, non-mlock()able.
175 * Note: mm/huge_memory.c VM_NO_THP depends on this definition.
177 #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP)
180 * mapping from the currently active vm_flags protection bits (the
181 * low four bits) to a page protection mask..
183 extern pgprot_t protection_map[16];
185 #define FAULT_FLAG_WRITE 0x01 /* Fault was a write access */
186 #define FAULT_FLAG_NONLINEAR 0x02 /* Fault was via a nonlinear mapping */
187 #define FAULT_FLAG_MKWRITE 0x04 /* Fault was mkwrite of existing pte */
188 #define FAULT_FLAG_ALLOW_RETRY 0x08 /* Retry fault if blocking */
189 #define FAULT_FLAG_RETRY_NOWAIT 0x10 /* Don't drop mmap_sem and wait when retrying */
190 #define FAULT_FLAG_KILLABLE 0x20 /* The fault task is in SIGKILL killable region */
191 #define FAULT_FLAG_TRIED 0x40 /* second try */
192 #define FAULT_FLAG_USER 0x80 /* The fault originated in userspace */
195 * vm_fault is filled by the the pagefault handler and passed to the vma's
196 * ->fault function. The vma's ->fault is responsible for returning a bitmask
197 * of VM_FAULT_xxx flags that give details about how the fault was handled.
199 * pgoff should be used in favour of virtual_address, if possible. If pgoff
200 * is used, one may implement ->remap_pages to get nonlinear mapping support.
203 unsigned int flags; /* FAULT_FLAG_xxx flags */
204 pgoff_t pgoff; /* Logical page offset based on vma */
205 void __user *virtual_address; /* Faulting virtual address */
207 struct page *page; /* ->fault handlers should return a
208 * page here, unless VM_FAULT_NOPAGE
209 * is set (which is also implied by
215 * These are the virtual MM functions - opening of an area, closing and
216 * unmapping it (needed to keep files on disk up-to-date etc), pointer
217 * to the functions called when a no-page or a wp-page exception occurs.
219 struct vm_operations_struct {
220 void (*open)(struct vm_area_struct * area);
221 void (*close)(struct vm_area_struct * area);
222 int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf);
224 /* notification that a previously read-only page is about to become
225 * writable, if an error is returned it will cause a SIGBUS */
226 int (*page_mkwrite)(struct vm_area_struct *vma, struct vm_fault *vmf);
228 /* called by access_process_vm when get_user_pages() fails, typically
229 * for use by special VMAs that can switch between memory and hardware
231 int (*access)(struct vm_area_struct *vma, unsigned long addr,
232 void *buf, int len, int write);
235 * set_policy() op must add a reference to any non-NULL @new mempolicy
236 * to hold the policy upon return. Caller should pass NULL @new to
237 * remove a policy and fall back to surrounding context--i.e. do not
238 * install a MPOL_DEFAULT policy, nor the task or system default
241 int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
244 * get_policy() op must add reference [mpol_get()] to any policy at
245 * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure
246 * in mm/mempolicy.c will do this automatically.
247 * get_policy() must NOT add a ref if the policy at (vma,addr) is not
248 * marked as MPOL_SHARED. vma policies are protected by the mmap_sem.
249 * If no [shared/vma] mempolicy exists at the addr, get_policy() op
250 * must return NULL--i.e., do not "fallback" to task or system default
253 struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
255 int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from,
256 const nodemask_t *to, unsigned long flags);
258 /* called by sys_remap_file_pages() to populate non-linear mapping */
259 int (*remap_pages)(struct vm_area_struct *vma, unsigned long addr,
260 unsigned long size, pgoff_t pgoff);
266 #define page_private(page) ((page)->private)
267 #define set_page_private(page, v) ((page)->private = (v))
269 /* It's valid only if the page is free path or free_list */
270 static inline void set_freepage_migratetype(struct page *page, int migratetype)
272 page->index = migratetype;
275 /* It's valid only if the page is free path or free_list */
276 static inline int get_freepage_migratetype(struct page *page)
282 * FIXME: take this include out, include page-flags.h in
283 * files which need it (119 of them)
285 #include <linux/page-flags.h>
286 #include <linux/huge_mm.h>
289 * Methods to modify the page usage count.
291 * What counts for a page usage:
292 * - cache mapping (page->mapping)
293 * - private data (page->private)
294 * - page mapped in a task's page tables, each mapping
295 * is counted separately
297 * Also, many kernel routines increase the page count before a critical
298 * routine so they can be sure the page doesn't go away from under them.
302 * Drop a ref, return true if the refcount fell to zero (the page has no users)
304 static inline int put_page_testzero(struct page *page)
306 VM_BUG_ON(atomic_read(&page->_count) == 0);
307 return atomic_dec_and_test(&page->_count);
311 * Try to grab a ref unless the page has a refcount of zero, return false if
313 * This can be called when MMU is off so it must not access
314 * any of the virtual mappings.
316 static inline int get_page_unless_zero(struct page *page)
318 return atomic_inc_not_zero(&page->_count);
322 * Try to drop a ref unless the page has a refcount of one, return false if
324 * This is to make sure that the refcount won't become zero after this drop.
325 * This can be called when MMU is off so it must not access
326 * any of the virtual mappings.
328 static inline int put_page_unless_one(struct page *page)
330 return atomic_add_unless(&page->_count, -1, 1);
333 extern int page_is_ram(unsigned long pfn);
335 /* Support for virtually mapped pages */
336 struct page *vmalloc_to_page(const void *addr);
337 unsigned long vmalloc_to_pfn(const void *addr);
340 * Determine if an address is within the vmalloc range
342 * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
343 * is no special casing required.
345 static inline int is_vmalloc_addr(const void *x)
348 unsigned long addr = (unsigned long)x;
350 return addr >= VMALLOC_START && addr < VMALLOC_END;
356 extern int is_vmalloc_or_module_addr(const void *x);
358 static inline int is_vmalloc_or_module_addr(const void *x)
364 static inline void compound_lock(struct page *page)
366 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
367 VM_BUG_ON(PageSlab(page));
368 bit_spin_lock(PG_compound_lock, &page->flags);
372 static inline void compound_unlock(struct page *page)
374 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
375 VM_BUG_ON(PageSlab(page));
376 bit_spin_unlock(PG_compound_lock, &page->flags);
380 static inline unsigned long compound_lock_irqsave(struct page *page)
382 unsigned long uninitialized_var(flags);
383 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
384 local_irq_save(flags);
390 static inline void compound_unlock_irqrestore(struct page *page,
393 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
394 compound_unlock(page);
395 local_irq_restore(flags);
399 static inline struct page *compound_head(struct page *page)
401 if (unlikely(PageTail(page)))
402 return page->first_page;
407 * The atomic page->_mapcount, starts from -1: so that transitions
408 * both from it and to it can be tracked, using atomic_inc_and_test
409 * and atomic_add_negative(-1).
411 static inline void page_mapcount_reset(struct page *page)
413 atomic_set(&(page)->_mapcount, -1);
416 static inline int page_mapcount(struct page *page)
418 return atomic_read(&(page)->_mapcount) + 1;
421 static inline int page_count(struct page *page)
423 return atomic_read(&compound_head(page)->_count);
426 #ifdef CONFIG_HUGETLB_PAGE
427 extern int PageHeadHuge(struct page *page_head);
428 #else /* CONFIG_HUGETLB_PAGE */
429 static inline int PageHeadHuge(struct page *page_head)
433 #endif /* CONFIG_HUGETLB_PAGE */
435 static inline bool __compound_tail_refcounted(struct page *page)
437 return !PageSlab(page) && !PageHeadHuge(page);
441 * This takes a head page as parameter and tells if the
442 * tail page reference counting can be skipped.
444 * For this to be safe, PageSlab and PageHeadHuge must remain true on
445 * any given page where they return true here, until all tail pins
446 * have been released.
448 static inline bool compound_tail_refcounted(struct page *page)
450 VM_BUG_ON(!PageHead(page));
451 return __compound_tail_refcounted(page);
454 static inline void get_huge_page_tail(struct page *page)
457 * __split_huge_page_refcount() cannot run from under us.
459 VM_BUG_ON(!PageTail(page));
460 VM_BUG_ON(page_mapcount(page) < 0);
461 VM_BUG_ON(atomic_read(&page->_count) != 0);
462 if (compound_tail_refcounted(page->first_page))
463 atomic_inc(&page->_mapcount);
466 extern bool __get_page_tail(struct page *page);
468 static inline void get_page(struct page *page)
470 if (unlikely(PageTail(page)))
471 if (likely(__get_page_tail(page)))
474 * Getting a normal page or the head of a compound page
475 * requires to already have an elevated page->_count.
477 VM_BUG_ON(atomic_read(&page->_count) <= 0);
478 atomic_inc(&page->_count);
481 static inline struct page *virt_to_head_page(const void *x)
483 struct page *page = virt_to_page(x);
484 return compound_head(page);
488 * Setup the page count before being freed into the page allocator for
489 * the first time (boot or memory hotplug)
491 static inline void init_page_count(struct page *page)
493 atomic_set(&page->_count, 1);
497 * PageBuddy() indicate that the page is free and in the buddy system
498 * (see mm/page_alloc.c).
500 * PAGE_BUDDY_MAPCOUNT_VALUE must be <= -2 but better not too close to
501 * -2 so that an underflow of the page_mapcount() won't be mistaken
502 * for a genuine PAGE_BUDDY_MAPCOUNT_VALUE. -128 can be created very
503 * efficiently by most CPU architectures.
505 #define PAGE_BUDDY_MAPCOUNT_VALUE (-128)
507 static inline int PageBuddy(struct page *page)
509 return atomic_read(&page->_mapcount) == PAGE_BUDDY_MAPCOUNT_VALUE;
512 static inline void __SetPageBuddy(struct page *page)
514 VM_BUG_ON(atomic_read(&page->_mapcount) != -1);
515 atomic_set(&page->_mapcount, PAGE_BUDDY_MAPCOUNT_VALUE);
518 static inline void __ClearPageBuddy(struct page *page)
520 VM_BUG_ON(!PageBuddy(page));
521 atomic_set(&page->_mapcount, -1);
524 void put_page(struct page *page);
525 void put_pages_list(struct list_head *pages);
527 void split_page(struct page *page, unsigned int order);
528 int split_free_page(struct page *page);
531 * Compound pages have a destructor function. Provide a
532 * prototype for that function and accessor functions.
533 * These are _only_ valid on the head of a PG_compound page.
535 typedef void compound_page_dtor(struct page *);
537 static inline void set_compound_page_dtor(struct page *page,
538 compound_page_dtor *dtor)
540 page[1].lru.next = (void *)dtor;
543 static inline compound_page_dtor *get_compound_page_dtor(struct page *page)
545 return (compound_page_dtor *)page[1].lru.next;
548 static inline int compound_order(struct page *page)
552 return (unsigned long)page[1].lru.prev;
555 static inline void set_compound_order(struct page *page, unsigned long order)
557 page[1].lru.prev = (void *)order;
562 * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when
563 * servicing faults for write access. In the normal case, do always want
564 * pte_mkwrite. But get_user_pages can cause write faults for mappings
565 * that do not have writing enabled, when used by access_process_vm.
567 static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
569 if (likely(vma->vm_flags & VM_WRITE))
570 pte = pte_mkwrite(pte);
576 * Multiple processes may "see" the same page. E.g. for untouched
577 * mappings of /dev/null, all processes see the same page full of
578 * zeroes, and text pages of executables and shared libraries have
579 * only one copy in memory, at most, normally.
581 * For the non-reserved pages, page_count(page) denotes a reference count.
582 * page_count() == 0 means the page is free. page->lru is then used for
583 * freelist management in the buddy allocator.
584 * page_count() > 0 means the page has been allocated.
586 * Pages are allocated by the slab allocator in order to provide memory
587 * to kmalloc and kmem_cache_alloc. In this case, the management of the
588 * page, and the fields in 'struct page' are the responsibility of mm/slab.c
589 * unless a particular usage is carefully commented. (the responsibility of
590 * freeing the kmalloc memory is the caller's, of course).
592 * A page may be used by anyone else who does a __get_free_page().
593 * In this case, page_count still tracks the references, and should only
594 * be used through the normal accessor functions. The top bits of page->flags
595 * and page->virtual store page management information, but all other fields
596 * are unused and could be used privately, carefully. The management of this
597 * page is the responsibility of the one who allocated it, and those who have
598 * subsequently been given references to it.
600 * The other pages (we may call them "pagecache pages") are completely
601 * managed by the Linux memory manager: I/O, buffers, swapping etc.
602 * The following discussion applies only to them.
604 * A pagecache page contains an opaque `private' member, which belongs to the
605 * page's address_space. Usually, this is the address of a circular list of
606 * the page's disk buffers. PG_private must be set to tell the VM to call
607 * into the filesystem to release these pages.
609 * A page may belong to an inode's memory mapping. In this case, page->mapping
610 * is the pointer to the inode, and page->index is the file offset of the page,
611 * in units of PAGE_CACHE_SIZE.
613 * If pagecache pages are not associated with an inode, they are said to be
614 * anonymous pages. These may become associated with the swapcache, and in that
615 * case PG_swapcache is set, and page->private is an offset into the swapcache.
617 * In either case (swapcache or inode backed), the pagecache itself holds one
618 * reference to the page. Setting PG_private should also increment the
619 * refcount. The each user mapping also has a reference to the page.
621 * The pagecache pages are stored in a per-mapping radix tree, which is
622 * rooted at mapping->page_tree, and indexed by offset.
623 * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space
624 * lists, we instead now tag pages as dirty/writeback in the radix tree.
626 * All pagecache pages may be subject to I/O:
627 * - inode pages may need to be read from disk,
628 * - inode pages which have been modified and are MAP_SHARED may need
629 * to be written back to the inode on disk,
630 * - anonymous pages (including MAP_PRIVATE file mappings) which have been
631 * modified may need to be swapped out to swap space and (later) to be read
636 * The zone field is never updated after free_area_init_core()
637 * sets it, so none of the operations on it need to be atomic.
640 /* Page flags: | [SECTION] | [NODE] | ZONE | [LAST_CPUPID] | ... | FLAGS | */
641 #define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH)
642 #define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH)
643 #define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH)
644 #define LAST_CPUPID_PGOFF (ZONES_PGOFF - LAST_CPUPID_WIDTH)
647 * Define the bit shifts to access each section. For non-existent
648 * sections we define the shift as 0; that plus a 0 mask ensures
649 * the compiler will optimise away reference to them.
651 #define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0))
652 #define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0))
653 #define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0))
654 #define LAST_CPUPID_PGSHIFT (LAST_CPUPID_PGOFF * (LAST_CPUPID_WIDTH != 0))
656 /* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allocator */
657 #ifdef NODE_NOT_IN_PAGE_FLAGS
658 #define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT)
659 #define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF)? \
660 SECTIONS_PGOFF : ZONES_PGOFF)
662 #define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT)
663 #define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF)? \
664 NODES_PGOFF : ZONES_PGOFF)
667 #define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0))
669 #if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
670 #error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
673 #define ZONES_MASK ((1UL << ZONES_WIDTH) - 1)
674 #define NODES_MASK ((1UL << NODES_WIDTH) - 1)
675 #define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1)
676 #define LAST_CPUPID_MASK ((1UL << LAST_CPUPID_WIDTH) - 1)
677 #define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1)
679 static inline enum zone_type page_zonenum(const struct page *page)
681 return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK;
684 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
685 #define SECTION_IN_PAGE_FLAGS
689 * The identification function is mainly used by the buddy allocator for
690 * determining if two pages could be buddies. We are not really identifying
691 * the zone since we could be using the section number id if we do not have
692 * node id available in page flags.
693 * We only guarantee that it will return the same value for two combinable
696 static inline int page_zone_id(struct page *page)
698 return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK;
701 static inline int zone_to_nid(struct zone *zone)
710 #ifdef NODE_NOT_IN_PAGE_FLAGS
711 extern int page_to_nid(const struct page *page);
713 static inline int page_to_nid(const struct page *page)
715 return (page->flags >> NODES_PGSHIFT) & NODES_MASK;
719 #ifdef CONFIG_NUMA_BALANCING
720 static inline int cpu_pid_to_cpupid(int cpu, int pid)
722 return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK);
725 static inline int cpupid_to_pid(int cpupid)
727 return cpupid & LAST__PID_MASK;
730 static inline int cpupid_to_cpu(int cpupid)
732 return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK;
735 static inline int cpupid_to_nid(int cpupid)
737 return cpu_to_node(cpupid_to_cpu(cpupid));
740 static inline bool cpupid_pid_unset(int cpupid)
742 return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK);
745 static inline bool cpupid_cpu_unset(int cpupid)
747 return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK);
750 static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid)
752 return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid);
755 #define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid)
756 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
757 static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
759 return xchg(&page->_last_cpupid, cpupid);
762 static inline int page_cpupid_last(struct page *page)
764 return page->_last_cpupid;
766 static inline void page_cpupid_reset_last(struct page *page)
768 page->_last_cpupid = -1;
771 static inline int page_cpupid_last(struct page *page)
773 return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
776 extern int page_cpupid_xchg_last(struct page *page, int cpupid);
778 static inline void page_cpupid_reset_last(struct page *page)
780 int cpupid = (1 << LAST_CPUPID_SHIFT) - 1;
782 page->flags &= ~(LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT);
783 page->flags |= (cpupid & LAST_CPUPID_MASK) << LAST_CPUPID_PGSHIFT;
785 #endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */
786 #else /* !CONFIG_NUMA_BALANCING */
787 static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
789 return page_to_nid(page); /* XXX */
792 static inline int page_cpupid_last(struct page *page)
794 return page_to_nid(page); /* XXX */
797 static inline int cpupid_to_nid(int cpupid)
802 static inline int cpupid_to_pid(int cpupid)
807 static inline int cpupid_to_cpu(int cpupid)
812 static inline int cpu_pid_to_cpupid(int nid, int pid)
817 static inline bool cpupid_pid_unset(int cpupid)
822 static inline void page_cpupid_reset_last(struct page *page)
826 static inline bool cpupid_match_pid(struct task_struct *task, int cpupid)
830 #endif /* CONFIG_NUMA_BALANCING */
832 static inline struct zone *page_zone(const struct page *page)
834 return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
837 #ifdef SECTION_IN_PAGE_FLAGS
838 static inline void set_page_section(struct page *page, unsigned long section)
840 page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT);
841 page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT;
844 static inline unsigned long page_to_section(const struct page *page)
846 return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
850 static inline void set_page_zone(struct page *page, enum zone_type zone)
852 page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
853 page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
856 static inline void set_page_node(struct page *page, unsigned long node)
858 page->flags &= ~(NODES_MASK << NODES_PGSHIFT);
859 page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
862 static inline void set_page_links(struct page *page, enum zone_type zone,
863 unsigned long node, unsigned long pfn)
865 set_page_zone(page, zone);
866 set_page_node(page, node);
867 #ifdef SECTION_IN_PAGE_FLAGS
868 set_page_section(page, pfn_to_section_nr(pfn));
873 * Some inline functions in vmstat.h depend on page_zone()
875 #include <linux/vmstat.h>
877 static __always_inline void *lowmem_page_address(const struct page *page)
879 return __va(PFN_PHYS(page_to_pfn(page)));
882 #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
883 #define HASHED_PAGE_VIRTUAL
886 #if defined(WANT_PAGE_VIRTUAL)
887 static inline void *page_address(const struct page *page)
889 return page->virtual;
891 static inline void set_page_address(struct page *page, void *address)
893 page->virtual = address;
895 #define page_address_init() do { } while(0)
898 #if defined(HASHED_PAGE_VIRTUAL)
899 void *page_address(const struct page *page);
900 void set_page_address(struct page *page, void *virtual);
901 void page_address_init(void);
904 #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
905 #define page_address(page) lowmem_page_address(page)
906 #define set_page_address(page, address) do { } while(0)
907 #define page_address_init() do { } while(0)
911 * On an anonymous page mapped into a user virtual memory area,
912 * page->mapping points to its anon_vma, not to a struct address_space;
913 * with the PAGE_MAPPING_ANON bit set to distinguish it. See rmap.h.
915 * On an anonymous page in a VM_MERGEABLE area, if CONFIG_KSM is enabled,
916 * the PAGE_MAPPING_KSM bit may be set along with the PAGE_MAPPING_ANON bit;
917 * and then page->mapping points, not to an anon_vma, but to a private
918 * structure which KSM associates with that merged page. See ksm.h.
920 * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is currently never used.
922 * Please note that, confusingly, "page_mapping" refers to the inode
923 * address_space which maps the page from disk; whereas "page_mapped"
924 * refers to user virtual address space into which the page is mapped.
926 #define PAGE_MAPPING_ANON 1
927 #define PAGE_MAPPING_KSM 2
928 #define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_KSM)
930 extern struct address_space *page_mapping(struct page *page);
932 /* Neutral page->mapping pointer to address_space or anon_vma or other */
933 static inline void *page_rmapping(struct page *page)
935 return (void *)((unsigned long)page->mapping & ~PAGE_MAPPING_FLAGS);
938 extern struct address_space *__page_file_mapping(struct page *);
941 struct address_space *page_file_mapping(struct page *page)
943 if (unlikely(PageSwapCache(page)))
944 return __page_file_mapping(page);
946 return page->mapping;
949 static inline int PageAnon(struct page *page)
951 return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0;
955 * Return the pagecache index of the passed page. Regular pagecache pages
956 * use ->index whereas swapcache pages use ->private
958 static inline pgoff_t page_index(struct page *page)
960 if (unlikely(PageSwapCache(page)))
961 return page_private(page);
965 extern pgoff_t __page_file_index(struct page *page);
968 * Return the file index of the page. Regular pagecache pages use ->index
969 * whereas swapcache pages use swp_offset(->private)
971 static inline pgoff_t page_file_index(struct page *page)
973 if (unlikely(PageSwapCache(page)))
974 return __page_file_index(page);
980 * Return true if this page is mapped into pagetables.
982 static inline int page_mapped(struct page *page)
984 return atomic_read(&(page)->_mapcount) >= 0;
988 * Different kinds of faults, as returned by handle_mm_fault().
989 * Used to decide whether a process gets delivered SIGBUS or
990 * just gets major/minor fault counters bumped up.
993 #define VM_FAULT_MINOR 0 /* For backwards compat. Remove me quickly. */
995 #define VM_FAULT_OOM 0x0001
996 #define VM_FAULT_SIGBUS 0x0002
997 #define VM_FAULT_MAJOR 0x0004
998 #define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
999 #define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
1000 #define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index encoded in upper bits */
1002 #define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */
1003 #define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */
1004 #define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
1005 #define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back to small */
1007 #define VM_FAULT_HWPOISON_LARGE_MASK 0xf000 /* encodes hpage index for large hwpoison */
1009 #define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_HWPOISON | \
1010 VM_FAULT_FALLBACK | VM_FAULT_HWPOISON_LARGE)
1012 /* Encode hstate index for a hwpoisoned large page */
1013 #define VM_FAULT_SET_HINDEX(x) ((x) << 12)
1014 #define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
1017 * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
1019 extern void pagefault_out_of_memory(void);
1021 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
1024 * Flags passed to show_mem() and show_free_areas() to suppress output in
1027 #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */
1029 extern void show_free_areas(unsigned int flags);
1030 extern bool skip_free_areas_node(unsigned int flags, int nid);
1032 int shmem_zero_setup(struct vm_area_struct *);
1034 extern int can_do_mlock(void);
1035 extern int user_shm_lock(size_t, struct user_struct *);
1036 extern void user_shm_unlock(size_t, struct user_struct *);
1039 * Parameter block passed down to zap_pte_range in exceptional cases.
1041 struct zap_details {
1042 struct vm_area_struct *nonlinear_vma; /* Check page->index if set */
1043 struct address_space *check_mapping; /* Check page->mapping if set */
1044 pgoff_t first_index; /* Lowest page->index to unmap */
1045 pgoff_t last_index; /* Highest page->index to unmap */
1048 struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
1051 int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
1052 unsigned long size);
1053 void zap_page_range(struct vm_area_struct *vma, unsigned long address,
1054 unsigned long size, struct zap_details *);
1055 void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
1056 unsigned long start, unsigned long end);
1059 * mm_walk - callbacks for walk_page_range
1060 * @pgd_entry: if set, called for each non-empty PGD (top-level) entry
1061 * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry
1062 * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
1063 * this handler is required to be able to handle
1064 * pmd_trans_huge() pmds. They may simply choose to
1065 * split_huge_page() instead of handling it explicitly.
1066 * @pte_entry: if set, called for each non-empty PTE (4th-level) entry
1067 * @pte_hole: if set, called for each hole at all levels
1068 * @hugetlb_entry: if set, called for each hugetlb entry
1069 * *Caution*: The caller must hold mmap_sem() if @hugetlb_entry
1072 * (see walk_page_range for more details)
1075 int (*pgd_entry)(pgd_t *pgd, unsigned long addr,
1076 unsigned long next, struct mm_walk *walk);
1077 int (*pud_entry)(pud_t *pud, unsigned long addr,
1078 unsigned long next, struct mm_walk *walk);
1079 int (*pmd_entry)(pmd_t *pmd, unsigned long addr,
1080 unsigned long next, struct mm_walk *walk);
1081 int (*pte_entry)(pte_t *pte, unsigned long addr,
1082 unsigned long next, struct mm_walk *walk);
1083 int (*pte_hole)(unsigned long addr, unsigned long next,
1084 struct mm_walk *walk);
1085 int (*hugetlb_entry)(pte_t *pte, unsigned long hmask,
1086 unsigned long addr, unsigned long next,
1087 struct mm_walk *walk);
1088 struct mm_struct *mm;
1092 int walk_page_range(unsigned long addr, unsigned long end,
1093 struct mm_walk *walk);
1094 void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
1095 unsigned long end, unsigned long floor, unsigned long ceiling);
1096 int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
1097 struct vm_area_struct *vma);
1098 void unmap_mapping_range(struct address_space *mapping,
1099 loff_t const holebegin, loff_t const holelen, int even_cows);
1100 int follow_pfn(struct vm_area_struct *vma, unsigned long address,
1101 unsigned long *pfn);
1102 int follow_phys(struct vm_area_struct *vma, unsigned long address,
1103 unsigned int flags, unsigned long *prot, resource_size_t *phys);
1104 int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
1105 void *buf, int len, int write);
1107 static inline void unmap_shared_mapping_range(struct address_space *mapping,
1108 loff_t const holebegin, loff_t const holelen)
1110 unmap_mapping_range(mapping, holebegin, holelen, 0);
1113 extern void truncate_pagecache(struct inode *inode, loff_t new);
1114 extern void truncate_setsize(struct inode *inode, loff_t newsize);
1115 void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);
1116 int truncate_inode_page(struct address_space *mapping, struct page *page);
1117 int generic_error_remove_page(struct address_space *mapping, struct page *page);
1118 int invalidate_inode_page(struct page *page);
1121 extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
1122 unsigned long address, unsigned int flags);
1123 extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
1124 unsigned long address, unsigned int fault_flags);
1126 static inline int handle_mm_fault(struct mm_struct *mm,
1127 struct vm_area_struct *vma, unsigned long address,
1130 /* should never happen if there's no MMU */
1132 return VM_FAULT_SIGBUS;
1134 static inline int fixup_user_fault(struct task_struct *tsk,
1135 struct mm_struct *mm, unsigned long address,
1136 unsigned int fault_flags)
1138 /* should never happen if there's no MMU */
1144 extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write);
1145 extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
1146 void *buf, int len, int write);
1148 long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
1149 unsigned long start, unsigned long nr_pages,
1150 unsigned int foll_flags, struct page **pages,
1151 struct vm_area_struct **vmas, int *nonblocking);
1152 long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
1153 unsigned long start, unsigned long nr_pages,
1154 int write, int force, struct page **pages,
1155 struct vm_area_struct **vmas);
1156 int get_user_pages_fast(unsigned long start, int nr_pages, int write,
1157 struct page **pages);
1159 int get_kernel_pages(const struct kvec *iov, int nr_pages, int write,
1160 struct page **pages);
1161 int get_kernel_page(unsigned long start, int write, struct page **pages);
1162 struct page *get_dump_page(unsigned long addr);
1164 extern int try_to_release_page(struct page * page, gfp_t gfp_mask);
1165 extern void do_invalidatepage(struct page *page, unsigned int offset,
1166 unsigned int length);
1168 int __set_page_dirty_nobuffers(struct page *page);
1169 int __set_page_dirty_no_writeback(struct page *page);
1170 int redirty_page_for_writepage(struct writeback_control *wbc,
1172 void account_page_dirtied(struct page *page, struct address_space *mapping);
1173 void account_page_writeback(struct page *page);
1174 int set_page_dirty(struct page *page);
1175 int set_page_dirty_lock(struct page *page);
1176 int clear_page_dirty_for_io(struct page *page);
1178 /* Is the vma a continuation of the stack vma above it? */
1179 static inline int vma_growsdown(struct vm_area_struct *vma, unsigned long addr)
1181 return vma && (vma->vm_end == addr) && (vma->vm_flags & VM_GROWSDOWN);
1184 static inline int stack_guard_page_start(struct vm_area_struct *vma,
1187 return (vma->vm_flags & VM_GROWSDOWN) &&
1188 (vma->vm_start == addr) &&
1189 !vma_growsdown(vma->vm_prev, addr);
1192 /* Is the vma a continuation of the stack vma below it? */
1193 static inline int vma_growsup(struct vm_area_struct *vma, unsigned long addr)
1195 return vma && (vma->vm_start == addr) && (vma->vm_flags & VM_GROWSUP);
1198 static inline int stack_guard_page_end(struct vm_area_struct *vma,
1201 return (vma->vm_flags & VM_GROWSUP) &&
1202 (vma->vm_end == addr) &&
1203 !vma_growsup(vma->vm_next, addr);
1207 vm_is_stack(struct task_struct *task, struct vm_area_struct *vma, int in_group);
1209 extern unsigned long move_page_tables(struct vm_area_struct *vma,
1210 unsigned long old_addr, struct vm_area_struct *new_vma,
1211 unsigned long new_addr, unsigned long len,
1212 bool need_rmap_locks);
1213 extern unsigned long change_protection(struct vm_area_struct *vma, unsigned long start,
1214 unsigned long end, pgprot_t newprot,
1215 int dirty_accountable, int prot_numa);
1216 extern int mprotect_fixup(struct vm_area_struct *vma,
1217 struct vm_area_struct **pprev, unsigned long start,
1218 unsigned long end, unsigned long newflags);
1221 * doesn't attempt to fault and will return short.
1223 int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
1224 struct page **pages);
1226 * per-process(per-mm_struct) statistics.
1228 static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
1230 long val = atomic_long_read(&mm->rss_stat.count[member]);
1232 #ifdef SPLIT_RSS_COUNTING
1234 * counter is updated in asynchronous manner and may go to minus.
1235 * But it's never be expected number for users.
1240 return (unsigned long)val;
1243 static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
1245 atomic_long_add(value, &mm->rss_stat.count[member]);
1248 static inline void inc_mm_counter(struct mm_struct *mm, int member)
1250 atomic_long_inc(&mm->rss_stat.count[member]);
1253 static inline void dec_mm_counter(struct mm_struct *mm, int member)
1255 atomic_long_dec(&mm->rss_stat.count[member]);
1258 static inline unsigned long get_mm_rss(struct mm_struct *mm)
1260 return get_mm_counter(mm, MM_FILEPAGES) +
1261 get_mm_counter(mm, MM_ANONPAGES);
1264 static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
1266 return max(mm->hiwater_rss, get_mm_rss(mm));
1269 static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
1271 return max(mm->hiwater_vm, mm->total_vm);
1274 static inline void update_hiwater_rss(struct mm_struct *mm)
1276 unsigned long _rss = get_mm_rss(mm);
1278 if ((mm)->hiwater_rss < _rss)
1279 (mm)->hiwater_rss = _rss;
1282 static inline void update_hiwater_vm(struct mm_struct *mm)
1284 if (mm->hiwater_vm < mm->total_vm)
1285 mm->hiwater_vm = mm->total_vm;
1288 static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
1289 struct mm_struct *mm)
1291 unsigned long hiwater_rss = get_mm_hiwater_rss(mm);
1293 if (*maxrss < hiwater_rss)
1294 *maxrss = hiwater_rss;
1297 #if defined(SPLIT_RSS_COUNTING)
1298 void sync_mm_rss(struct mm_struct *mm);
1300 static inline void sync_mm_rss(struct mm_struct *mm)
1305 int vma_wants_writenotify(struct vm_area_struct *vma);
1307 extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
1309 static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
1313 __cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl));
1317 #ifdef __PAGETABLE_PUD_FOLDED
1318 static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd,
1319 unsigned long address)
1324 int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
1327 #ifdef __PAGETABLE_PMD_FOLDED
1328 static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
1329 unsigned long address)
1334 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);
1337 int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
1338 pmd_t *pmd, unsigned long address);
1339 int __pte_alloc_kernel(pmd_t *pmd, unsigned long address);
1342 * The following ifdef needed to get the 4level-fixup.h header to work.
1343 * Remove it when 4level-fixup.h has been removed.
1345 #if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK)
1346 static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
1348 return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))?
1349 NULL: pud_offset(pgd, address);
1352 static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
1354 return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
1355 NULL: pmd_offset(pud, address);
1357 #endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */
1359 #if USE_SPLIT_PTE_PTLOCKS
1360 #if ALLOC_SPLIT_PTLOCKS
1361 void __init ptlock_cache_init(void);
1362 extern bool ptlock_alloc(struct page *page);
1363 extern void ptlock_free(struct page *page);
1365 static inline spinlock_t *ptlock_ptr(struct page *page)
1369 #else /* ALLOC_SPLIT_PTLOCKS */
1370 static inline void ptlock_cache_init(void)
1374 static inline bool ptlock_alloc(struct page *page)
1379 static inline void ptlock_free(struct page *page)
1383 static inline spinlock_t *ptlock_ptr(struct page *page)
1387 #endif /* ALLOC_SPLIT_PTLOCKS */
1389 static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
1391 return ptlock_ptr(pmd_page(*pmd));
1394 static inline bool ptlock_init(struct page *page)
1397 * prep_new_page() initialize page->private (and therefore page->ptl)
1398 * with 0. Make sure nobody took it in use in between.
1400 * It can happen if arch try to use slab for page table allocation:
1401 * slab code uses page->slab_cache and page->first_page (for tail
1402 * pages), which share storage with page->ptl.
1404 VM_BUG_ON(*(unsigned long *)&page->ptl);
1405 if (!ptlock_alloc(page))
1407 spin_lock_init(ptlock_ptr(page));
1411 /* Reset page->mapping so free_pages_check won't complain. */
1412 static inline void pte_lock_deinit(struct page *page)
1414 page->mapping = NULL;
1418 #else /* !USE_SPLIT_PTE_PTLOCKS */
1420 * We use mm->page_table_lock to guard all pagetable pages of the mm.
1422 static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
1424 return &mm->page_table_lock;
1426 static inline void ptlock_cache_init(void) {}
1427 static inline bool ptlock_init(struct page *page) { return true; }
1428 static inline void pte_lock_deinit(struct page *page) {}
1429 #endif /* USE_SPLIT_PTE_PTLOCKS */
1431 static inline void pgtable_init(void)
1433 ptlock_cache_init();
1434 pgtable_cache_init();
1437 static inline bool pgtable_page_ctor(struct page *page)
1439 inc_zone_page_state(page, NR_PAGETABLE);
1440 return ptlock_init(page);
1443 static inline void pgtable_page_dtor(struct page *page)
1445 pte_lock_deinit(page);
1446 dec_zone_page_state(page, NR_PAGETABLE);
1449 #define pte_offset_map_lock(mm, pmd, address, ptlp) \
1451 spinlock_t *__ptl = pte_lockptr(mm, pmd); \
1452 pte_t *__pte = pte_offset_map(pmd, address); \
1458 #define pte_unmap_unlock(pte, ptl) do { \
1463 #define pte_alloc_map(mm, vma, pmd, address) \
1464 ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, vma, \
1466 NULL: pte_offset_map(pmd, address))
1468 #define pte_alloc_map_lock(mm, pmd, address, ptlp) \
1469 ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, NULL, \
1471 NULL: pte_offset_map_lock(mm, pmd, address, ptlp))
1473 #define pte_alloc_kernel(pmd, address) \
1474 ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd, address))? \
1475 NULL: pte_offset_kernel(pmd, address))
1477 #if USE_SPLIT_PMD_PTLOCKS
1479 static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
1481 return ptlock_ptr(virt_to_page(pmd));
1484 static inline bool pgtable_pmd_page_ctor(struct page *page)
1486 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1487 page->pmd_huge_pte = NULL;
1489 return ptlock_init(page);
1492 static inline void pgtable_pmd_page_dtor(struct page *page)
1494 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1495 VM_BUG_ON(page->pmd_huge_pte);
1500 #define pmd_huge_pte(mm, pmd) (virt_to_page(pmd)->pmd_huge_pte)
1504 static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
1506 return &mm->page_table_lock;
1509 static inline bool pgtable_pmd_page_ctor(struct page *page) { return true; }
1510 static inline void pgtable_pmd_page_dtor(struct page *page) {}
1512 #define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte)
1516 static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd)
1518 spinlock_t *ptl = pmd_lockptr(mm, pmd);
1523 extern void free_area_init(unsigned long * zones_size);
1524 extern void free_area_init_node(int nid, unsigned long * zones_size,
1525 unsigned long zone_start_pfn, unsigned long *zholes_size);
1526 extern void free_initmem(void);
1529 * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
1530 * into the buddy system. The freed pages will be poisoned with pattern
1531 * "poison" if it's within range [0, UCHAR_MAX].
1532 * Return pages freed into the buddy system.
1534 extern unsigned long free_reserved_area(void *start, void *end,
1535 int poison, char *s);
1537 #ifdef CONFIG_HIGHMEM
1539 * Free a highmem page into the buddy system, adjusting totalhigh_pages
1540 * and totalram_pages.
1542 extern void free_highmem_page(struct page *page);
1545 extern void adjust_managed_page_count(struct page *page, long count);
1546 extern void mem_init_print_info(const char *str);
1548 /* Free the reserved page into the buddy system, so it gets managed. */
1549 static inline void __free_reserved_page(struct page *page)
1551 ClearPageReserved(page);
1552 init_page_count(page);
1556 static inline void free_reserved_page(struct page *page)
1558 __free_reserved_page(page);
1559 adjust_managed_page_count(page, 1);
1562 static inline void mark_page_reserved(struct page *page)
1564 SetPageReserved(page);
1565 adjust_managed_page_count(page, -1);
1569 * Default method to free all the __init memory into the buddy system.
1570 * The freed pages will be poisoned with pattern "poison" if it's within
1571 * range [0, UCHAR_MAX].
1572 * Return pages freed into the buddy system.
1574 static inline unsigned long free_initmem_default(int poison)
1576 extern char __init_begin[], __init_end[];
1578 return free_reserved_area(&__init_begin, &__init_end,
1579 poison, "unused kernel");
1582 static inline unsigned long get_num_physpages(void)
1585 unsigned long phys_pages = 0;
1587 for_each_online_node(nid)
1588 phys_pages += node_present_pages(nid);
1593 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
1595 * With CONFIG_HAVE_MEMBLOCK_NODE_MAP set, an architecture may initialise its
1596 * zones, allocate the backing mem_map and account for memory holes in a more
1597 * architecture independent manner. This is a substitute for creating the
1598 * zone_sizes[] and zholes_size[] arrays and passing them to
1599 * free_area_init_node()
1601 * An architecture is expected to register range of page frames backed by
1602 * physical memory with memblock_add[_node]() before calling
1603 * free_area_init_nodes() passing in the PFN each zone ends at. At a basic
1604 * usage, an architecture is expected to do something like
1606 * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn,
1608 * for_each_valid_physical_page_range()
1609 * memblock_add_node(base, size, nid)
1610 * free_area_init_nodes(max_zone_pfns);
1612 * free_bootmem_with_active_regions() calls free_bootmem_node() for each
1613 * registered physical page range. Similarly
1614 * sparse_memory_present_with_active_regions() calls memory_present() for
1615 * each range when SPARSEMEM is enabled.
1617 * See mm/page_alloc.c for more information on each function exposed by
1618 * CONFIG_HAVE_MEMBLOCK_NODE_MAP.
1620 extern void free_area_init_nodes(unsigned long *max_zone_pfn);
1621 unsigned long node_map_pfn_alignment(void);
1622 unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn,
1623 unsigned long end_pfn);
1624 extern unsigned long absent_pages_in_range(unsigned long start_pfn,
1625 unsigned long end_pfn);
1626 extern void get_pfn_range_for_nid(unsigned int nid,
1627 unsigned long *start_pfn, unsigned long *end_pfn);
1628 extern unsigned long find_min_pfn_with_active_regions(void);
1629 extern void free_bootmem_with_active_regions(int nid,
1630 unsigned long max_low_pfn);
1631 extern void sparse_memory_present_with_active_regions(int nid);
1633 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
1635 #if !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) && \
1636 !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID)
1637 static inline int __early_pfn_to_nid(unsigned long pfn)
1642 /* please see mm/page_alloc.c */
1643 extern int __meminit early_pfn_to_nid(unsigned long pfn);
1644 #ifdef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
1645 /* there is a per-arch backend function. */
1646 extern int __meminit __early_pfn_to_nid(unsigned long pfn);
1647 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
1650 extern void set_dma_reserve(unsigned long new_dma_reserve);
1651 extern void memmap_init_zone(unsigned long, int, unsigned long,
1652 unsigned long, enum memmap_context);
1653 extern void setup_per_zone_wmarks(void);
1654 extern int __meminit init_per_zone_wmark_min(void);
1655 extern void mem_init(void);
1656 extern void __init mmap_init(void);
1657 extern void show_mem(unsigned int flags);
1658 extern void si_meminfo(struct sysinfo * val);
1659 extern void si_meminfo_node(struct sysinfo *val, int nid);
1661 extern __printf(3, 4)
1662 void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...);
1664 extern void setup_per_cpu_pageset(void);
1666 extern void zone_pcp_update(struct zone *zone);
1667 extern void zone_pcp_reset(struct zone *zone);
1670 extern int min_free_kbytes;
1673 extern atomic_long_t mmap_pages_allocated;
1674 extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
1676 /* interval_tree.c */
1677 void vma_interval_tree_insert(struct vm_area_struct *node,
1678 struct rb_root *root);
1679 void vma_interval_tree_insert_after(struct vm_area_struct *node,
1680 struct vm_area_struct *prev,
1681 struct rb_root *root);
1682 void vma_interval_tree_remove(struct vm_area_struct *node,
1683 struct rb_root *root);
1684 struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root *root,
1685 unsigned long start, unsigned long last);
1686 struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
1687 unsigned long start, unsigned long last);
1689 #define vma_interval_tree_foreach(vma, root, start, last) \
1690 for (vma = vma_interval_tree_iter_first(root, start, last); \
1691 vma; vma = vma_interval_tree_iter_next(vma, start, last))
1693 static inline void vma_nonlinear_insert(struct vm_area_struct *vma,
1694 struct list_head *list)
1696 list_add_tail(&vma->shared.nonlinear, list);
1699 void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
1700 struct rb_root *root);
1701 void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
1702 struct rb_root *root);
1703 struct anon_vma_chain *anon_vma_interval_tree_iter_first(
1704 struct rb_root *root, unsigned long start, unsigned long last);
1705 struct anon_vma_chain *anon_vma_interval_tree_iter_next(
1706 struct anon_vma_chain *node, unsigned long start, unsigned long last);
1707 #ifdef CONFIG_DEBUG_VM_RB
1708 void anon_vma_interval_tree_verify(struct anon_vma_chain *node);
1711 #define anon_vma_interval_tree_foreach(avc, root, start, last) \
1712 for (avc = anon_vma_interval_tree_iter_first(root, start, last); \
1713 avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))
1716 extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin);
1717 extern int vma_adjust(struct vm_area_struct *vma, unsigned long start,
1718 unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert);
1719 extern struct vm_area_struct *vma_merge(struct mm_struct *,
1720 struct vm_area_struct *prev, unsigned long addr, unsigned long end,
1721 unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t,
1722 struct mempolicy *);
1723 extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
1724 extern int split_vma(struct mm_struct *,
1725 struct vm_area_struct *, unsigned long addr, int new_below);
1726 extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
1727 extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *,
1728 struct rb_node **, struct rb_node *);
1729 extern void unlink_file_vma(struct vm_area_struct *);
1730 extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
1731 unsigned long addr, unsigned long len, pgoff_t pgoff,
1732 bool *need_rmap_locks);
1733 extern void exit_mmap(struct mm_struct *);
1735 extern int mm_take_all_locks(struct mm_struct *mm);
1736 extern void mm_drop_all_locks(struct mm_struct *mm);
1738 extern void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
1739 extern struct file *get_mm_exe_file(struct mm_struct *mm);
1741 extern int may_expand_vm(struct mm_struct *mm, unsigned long npages);
1742 extern int install_special_mapping(struct mm_struct *mm,
1743 unsigned long addr, unsigned long len,
1744 unsigned long flags, struct page **pages);
1746 extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1748 extern unsigned long mmap_region(struct file *file, unsigned long addr,
1749 unsigned long len, vm_flags_t vm_flags, unsigned long pgoff);
1750 extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
1751 unsigned long len, unsigned long prot, unsigned long flags,
1752 unsigned long pgoff, unsigned long *populate);
1753 extern int do_munmap(struct mm_struct *, unsigned long, size_t);
1756 extern int __mm_populate(unsigned long addr, unsigned long len,
1758 static inline void mm_populate(unsigned long addr, unsigned long len)
1761 (void) __mm_populate(addr, len, 1);
1764 static inline void mm_populate(unsigned long addr, unsigned long len) {}
1767 /* These take the mm semaphore themselves */
1768 extern unsigned long vm_brk(unsigned long, unsigned long);
1769 extern int vm_munmap(unsigned long, size_t);
1770 extern unsigned long vm_mmap(struct file *, unsigned long,
1771 unsigned long, unsigned long,
1772 unsigned long, unsigned long);
1774 struct vm_unmapped_area_info {
1775 #define VM_UNMAPPED_AREA_TOPDOWN 1
1776 unsigned long flags;
1777 unsigned long length;
1778 unsigned long low_limit;
1779 unsigned long high_limit;
1780 unsigned long align_mask;
1781 unsigned long align_offset;
1784 extern unsigned long unmapped_area(struct vm_unmapped_area_info *info);
1785 extern unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info);
1788 * Search for an unmapped address range.
1790 * We are looking for a range that:
1791 * - does not intersect with any VMA;
1792 * - is contained within the [low_limit, high_limit) interval;
1793 * - is at least the desired size.
1794 * - satisfies (begin_addr & align_mask) == (align_offset & align_mask)
1796 static inline unsigned long
1797 vm_unmapped_area(struct vm_unmapped_area_info *info)
1799 if (!(info->flags & VM_UNMAPPED_AREA_TOPDOWN))
1800 return unmapped_area(info);
1802 return unmapped_area_topdown(info);
1806 extern void truncate_inode_pages(struct address_space *, loff_t);
1807 extern void truncate_inode_pages_range(struct address_space *,
1808 loff_t lstart, loff_t lend);
1810 /* generic vm_area_ops exported for stackable file systems */
1811 extern int filemap_fault(struct vm_area_struct *, struct vm_fault *);
1812 extern int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1814 /* mm/page-writeback.c */
1815 int write_one_page(struct page *page, int wait);
1816 void task_dirty_inc(struct task_struct *tsk);
1819 #define VM_MAX_READAHEAD 128 /* kbytes */
1820 #define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */
1822 int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
1823 pgoff_t offset, unsigned long nr_to_read);
1825 void page_cache_sync_readahead(struct address_space *mapping,
1826 struct file_ra_state *ra,
1829 unsigned long size);
1831 void page_cache_async_readahead(struct address_space *mapping,
1832 struct file_ra_state *ra,
1836 unsigned long size);
1838 unsigned long max_sane_readahead(unsigned long nr);
1839 unsigned long ra_submit(struct file_ra_state *ra,
1840 struct address_space *mapping,
1843 /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
1844 extern int expand_stack(struct vm_area_struct *vma, unsigned long address);
1846 /* CONFIG_STACK_GROWSUP still needs to to grow downwards at some places */
1847 extern int expand_downwards(struct vm_area_struct *vma,
1848 unsigned long address);
1850 extern int expand_upwards(struct vm_area_struct *vma, unsigned long address);
1852 #define expand_upwards(vma, address) do { } while (0)
1855 /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */
1856 extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr);
1857 extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
1858 struct vm_area_struct **pprev);
1860 /* Look up the first VMA which intersects the interval start_addr..end_addr-1,
1861 NULL if none. Assume start_addr < end_addr. */
1862 static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr)
1864 struct vm_area_struct * vma = find_vma(mm,start_addr);
1866 if (vma && end_addr <= vma->vm_start)
1871 static inline unsigned long vma_pages(struct vm_area_struct *vma)
1873 return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
1876 /* Look up the first VMA which exactly match the interval vm_start ... vm_end */
1877 static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
1878 unsigned long vm_start, unsigned long vm_end)
1880 struct vm_area_struct *vma = find_vma(mm, vm_start);
1882 if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
1889 pgprot_t vm_get_page_prot(unsigned long vm_flags);
1891 static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
1897 #ifdef CONFIG_ARCH_USES_NUMA_PROT_NONE
1898 unsigned long change_prot_numa(struct vm_area_struct *vma,
1899 unsigned long start, unsigned long end);
1902 struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr);
1903 int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
1904 unsigned long pfn, unsigned long size, pgprot_t);
1905 int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
1906 int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
1908 int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
1910 int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
1913 struct page *follow_page_mask(struct vm_area_struct *vma,
1914 unsigned long address, unsigned int foll_flags,
1915 unsigned int *page_mask);
1917 static inline struct page *follow_page(struct vm_area_struct *vma,
1918 unsigned long address, unsigned int foll_flags)
1920 unsigned int unused_page_mask;
1921 return follow_page_mask(vma, address, foll_flags, &unused_page_mask);
1924 #define FOLL_WRITE 0x01 /* check pte is writable */
1925 #define FOLL_TOUCH 0x02 /* mark page accessed */
1926 #define FOLL_GET 0x04 /* do get_page on page */
1927 #define FOLL_DUMP 0x08 /* give error on hole if it would be zero */
1928 #define FOLL_FORCE 0x10 /* get_user_pages read/write w/o permission */
1929 #define FOLL_NOWAIT 0x20 /* if a disk transfer is needed, start the IO
1930 * and return without waiting upon it */
1931 #define FOLL_MLOCK 0x40 /* mark page as mlocked */
1932 #define FOLL_SPLIT 0x80 /* don't return transhuge pages, split them */
1933 #define FOLL_HWPOISON 0x100 /* check page is hwpoisoned */
1934 #define FOLL_NUMA 0x200 /* force NUMA hinting page fault */
1935 #define FOLL_MIGRATION 0x400 /* wait for page to replace migration entry */
1937 typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr,
1939 extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
1940 unsigned long size, pte_fn_t fn, void *data);
1942 #ifdef CONFIG_PROC_FS
1943 void vm_stat_account(struct mm_struct *, unsigned long, struct file *, long);
1945 static inline void vm_stat_account(struct mm_struct *mm,
1946 unsigned long flags, struct file *file, long pages)
1948 mm->total_vm += pages;
1950 #endif /* CONFIG_PROC_FS */
1952 #ifdef CONFIG_DEBUG_PAGEALLOC
1953 extern void kernel_map_pages(struct page *page, int numpages, int enable);
1954 #ifdef CONFIG_HIBERNATION
1955 extern bool kernel_page_present(struct page *page);
1956 #endif /* CONFIG_HIBERNATION */
1959 kernel_map_pages(struct page *page, int numpages, int enable) {}
1960 #ifdef CONFIG_HIBERNATION
1961 static inline bool kernel_page_present(struct page *page) { return true; }
1962 #endif /* CONFIG_HIBERNATION */
1965 extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
1966 #ifdef __HAVE_ARCH_GATE_AREA
1967 int in_gate_area_no_mm(unsigned long addr);
1968 int in_gate_area(struct mm_struct *mm, unsigned long addr);
1970 int in_gate_area_no_mm(unsigned long addr);
1971 #define in_gate_area(mm, addr) ({(void)mm; in_gate_area_no_mm(addr);})
1972 #endif /* __HAVE_ARCH_GATE_AREA */
1974 #ifdef CONFIG_SYSCTL
1975 extern int sysctl_drop_caches;
1976 int drop_caches_sysctl_handler(struct ctl_table *, int,
1977 void __user *, size_t *, loff_t *);
1980 unsigned long shrink_slab(struct shrink_control *shrink,
1981 unsigned long nr_pages_scanned,
1982 unsigned long lru_pages);
1985 #define randomize_va_space 0
1987 extern int randomize_va_space;
1990 const char * arch_vma_name(struct vm_area_struct *vma);
1991 void print_vma_addr(char *prefix, unsigned long rip);
1993 void sparse_mem_maps_populate_node(struct page **map_map,
1994 unsigned long pnum_begin,
1995 unsigned long pnum_end,
1996 unsigned long map_count,
1999 struct page *sparse_mem_map_populate(unsigned long pnum, int nid);
2000 pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
2001 pud_t *vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node);
2002 pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
2003 pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node);
2004 void *vmemmap_alloc_block(unsigned long size, int node);
2005 void *vmemmap_alloc_block_buf(unsigned long size, int node);
2006 void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
2007 int vmemmap_populate_basepages(unsigned long start, unsigned long end,
2009 int vmemmap_populate(unsigned long start, unsigned long end, int node);
2010 void vmemmap_populate_print_last(void);
2011 #ifdef CONFIG_MEMORY_HOTPLUG
2012 void vmemmap_free(unsigned long start, unsigned long end);
2014 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
2015 unsigned long size);
2018 MF_COUNT_INCREASED = 1 << 0,
2019 MF_ACTION_REQUIRED = 1 << 1,
2020 MF_MUST_KILL = 1 << 2,
2021 MF_SOFT_OFFLINE = 1 << 3,
2023 extern int memory_failure(unsigned long pfn, int trapno, int flags);
2024 extern void memory_failure_queue(unsigned long pfn, int trapno, int flags);
2025 extern int unpoison_memory(unsigned long pfn);
2026 extern int sysctl_memory_failure_early_kill;
2027 extern int sysctl_memory_failure_recovery;
2028 extern void shake_page(struct page *p, int access);
2029 extern atomic_long_t num_poisoned_pages;
2030 extern int soft_offline_page(struct page *page, int flags);
2032 extern void dump_page(struct page *page);
2034 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS)
2035 extern void clear_huge_page(struct page *page,
2037 unsigned int pages_per_huge_page);
2038 extern void copy_user_huge_page(struct page *dst, struct page *src,
2039 unsigned long addr, struct vm_area_struct *vma,
2040 unsigned int pages_per_huge_page);
2041 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
2043 #ifdef CONFIG_DEBUG_PAGEALLOC
2044 extern unsigned int _debug_guardpage_minorder;
2046 static inline unsigned int debug_guardpage_minorder(void)
2048 return _debug_guardpage_minorder;
2051 static inline bool page_is_guard(struct page *page)
2053 return test_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags);
2056 static inline unsigned int debug_guardpage_minorder(void) { return 0; }
2057 static inline bool page_is_guard(struct page *page) { return false; }
2058 #endif /* CONFIG_DEBUG_PAGEALLOC */
2060 #if MAX_NUMNODES > 1
2061 void __init setup_nr_node_ids(void);
2063 static inline void setup_nr_node_ids(void) {}
2066 #endif /* __KERNEL__ */
2067 #endif /* _LINUX_MM_H */