#ifndef _LINUX_MM_H #define _LINUX_MM_H #include #include #ifdef __KERNEL__ #include #include #include #include #include #include #include struct mempolicy; struct anon_vma; #ifndef CONFIG_DISCONTIGMEM /* Don't use mapnrs, do it properly */ extern unsigned long max_mapnr; #endif extern unsigned long num_physpages; extern void * high_memory; extern unsigned long vmalloc_earlyreserve; extern int page_cluster; #ifdef CONFIG_SYSCTL extern int sysctl_legacy_va_layout; #else #define sysctl_legacy_va_layout 0 #endif #include #include #include #include #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n)) /* * Linux kernel virtual memory manager primitives. * The idea being to have a "virtual" mm in the same way * we have a virtual fs - giving a cleaner interface to the * mm details, and allowing different kinds of memory mappings * (from shared memory to executable loading to arbitrary * mmap() functions). */ /* * This struct defines a memory VMM memory area. There is one of these * per VM-area/task. A VM area is any part of the process virtual memory * space that has a special rule for the page-fault handlers (ie a shared * library, the executable area etc). */ struct vm_area_struct { struct mm_struct * vm_mm; /* The address space we belong to. */ unsigned long vm_start; /* Our start address within vm_mm. */ unsigned long vm_end; /* The first byte after our end address within vm_mm. */ /* linked list of VM areas per task, sorted by address */ struct vm_area_struct *vm_next; pgprot_t vm_page_prot; /* Access permissions of this VMA. */ unsigned long vm_flags; /* Flags, listed below. */ struct rb_node vm_rb; /* * For areas with an address space and backing store, * linkage into the address_space->i_mmap prio tree, or * linkage to the list of like vmas hanging off its node, or * linkage of vma in the address_space->i_mmap_nonlinear list. */ union { struct { struct list_head list; void *parent; /* aligns with prio_tree_node parent */ struct vm_area_struct *head; } vm_set; struct raw_prio_tree_node prio_tree_node; } shared; /* * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma * list, after a COW of one of the file pages. A MAP_SHARED vma * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack * or brk vma (with NULL file) can only be in an anon_vma list. */ struct list_head anon_vma_node; /* Serialized by anon_vma->lock */ struct anon_vma *anon_vma; /* Serialized by page_table_lock */ /* Function pointers to deal with this struct. */ struct vm_operations_struct * vm_ops; /* Information about our backing store: */ unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE units, *not* PAGE_CACHE_SIZE */ struct file * vm_file; /* File we map to (can be NULL). */ void * vm_private_data; /* was vm_pte (shared mem) */ unsigned long vm_truncate_count;/* truncate_count or restart_addr */ #ifndef CONFIG_MMU atomic_t vm_usage; /* refcount (VMAs shared if !MMU) */ #endif #ifdef CONFIG_NUMA struct mempolicy *vm_policy; /* NUMA policy for the VMA */ #endif }; /* * This struct defines the per-mm list of VMAs for uClinux. If CONFIG_MMU is * disabled, then there's a single shared list of VMAs maintained by the * system, and mm's subscribe to these individually */ struct vm_list_struct { struct vm_list_struct *next; struct vm_area_struct *vma; }; #ifndef CONFIG_MMU extern struct rb_root nommu_vma_tree; extern struct rw_semaphore nommu_vma_sem; extern unsigned int kobjsize(const void *objp); #endif /* * vm_flags.. */ #define VM_READ 0x00000001 /* currently active flags */ #define VM_WRITE 0x00000002 #define VM_EXEC 0x00000004 #define VM_SHARED 0x00000008 /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */ #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */ #define VM_MAYWRITE 0x00000020 #define VM_MAYEXEC 0x00000040 #define VM_MAYSHARE 0x00000080 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */ #define VM_GROWSUP 0x00000200 #define VM_SHM 0x00000000 /* Means nothing: delete it later */ #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */ #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */ #define VM_EXECUTABLE 0x00001000 #define VM_LOCKED 0x00002000 #define VM_IO 0x00004000 /* Memory mapped I/O or similar */ /* Used by sys_madvise() */ #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */ #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */ #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ #define VM_RESERVED 0x00080000 /* Count as reserved_vm like IO */ #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */ #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ #define VM_NONLINEAR 0x00800000 /* Is non-linear (remap_file_pages) */ #define VM_MAPPED_COPY 0x01000000 /* T if mapped copy of data (nommu mmap) */ #define VM_INCOMPLETE 0x02000000 /* Strange partial PFN mapping marker */ #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */ #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS #endif #ifdef CONFIG_STACK_GROWSUP #define VM_STACK_FLAGS (VM_GROWSUP | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) #else #define VM_STACK_FLAGS (VM_GROWSDOWN | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) #endif #define VM_READHINTMASK (VM_SEQ_READ | VM_RAND_READ) #define VM_ClearReadHint(v) (v)->vm_flags &= ~VM_READHINTMASK #define VM_NormalReadHint(v) (!((v)->vm_flags & VM_READHINTMASK)) #define VM_SequentialReadHint(v) ((v)->vm_flags & VM_SEQ_READ) #define VM_RandomReadHint(v) ((v)->vm_flags & VM_RAND_READ) /* * mapping from the currently active vm_flags protection bits (the * low four bits) to a page protection mask.. */ extern pgprot_t protection_map[16]; /* * These are the virtual MM functions - opening of an area, closing and * unmapping it (needed to keep files on disk up-to-date etc), pointer * to the functions called when a no-page or a wp-page exception occurs. */ struct vm_operations_struct { void (*open)(struct vm_area_struct * area); void (*close)(struct vm_area_struct * area); struct page * (*nopage)(struct vm_area_struct * area, unsigned long address, int *type); int (*populate)(struct vm_area_struct * area, unsigned long address, unsigned long len, pgprot_t prot, unsigned long pgoff, int nonblock); #ifdef CONFIG_NUMA int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); struct mempolicy *(*get_policy)(struct vm_area_struct *vma, unsigned long addr); #endif }; struct mmu_gather; struct inode; /* * Each physical page in the system has a struct page associated with * it to keep track of whatever it is we are using the page for at the * moment. Note that we have no way to track which tasks are using * a page. */ struct page { unsigned long flags; /* Atomic flags, some possibly * updated asynchronously */ atomic_t _count; /* Usage count, see below. */ atomic_t _mapcount; /* Count of ptes mapped in mms, * to show when page is mapped * & limit reverse map searches. */ union { unsigned long private; /* Mapping-private opaque data: * usually used for buffer_heads * if PagePrivate set; used for * swp_entry_t if PageSwapCache * When page is free, this indicates * order in the buddy system. */ #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS spinlock_t ptl; #endif } u; struct address_space *mapping; /* If low bit clear, points to * inode address_space, or NULL. * If page mapped as anonymous * memory, low bit is set, and * it points to anon_vma object: * see PAGE_MAPPING_ANON below. */ pgoff_t index; /* Our offset within mapping. */ struct list_head lru; /* Pageout list, eg. active_list * protected by zone->lru_lock ! */ /* * On machines where all RAM is mapped into kernel address space, * we can simply calculate the virtual address. On machines with * highmem some memory is mapped into kernel virtual memory * dynamically, so we need a place to store that address. * Note that this field could be 16 bits on x86 ... ;) * * Architectures with slow multiplication can define * WANT_PAGE_VIRTUAL in asm/page.h */ #if defined(WANT_PAGE_VIRTUAL) void *virtual; /* Kernel virtual address (NULL if not kmapped, ie. highmem) */ #endif /* WANT_PAGE_VIRTUAL */ }; #define page_private(page) ((page)->u.private) #define set_page_private(page, v) ((page)->u.private = (v)) /* * FIXME: take this include out, include page-flags.h in * files which need it (119 of them) */ #include /* * Methods to modify the page usage count. * * What counts for a page usage: * - cache mapping (page->mapping) * - private data (page->private) * - page mapped in a task's page tables, each mapping * is counted separately * * Also, many kernel routines increase the page count before a critical * routine so they can be sure the page doesn't go away from under them. * * Since 2.6.6 (approx), a free page has ->_count = -1. This is so that we * can use atomic_add_negative(-1, page->_count) to detect when the page * becomes free and so that we can also use atomic_inc_and_test to atomically * detect when we just tried to grab a ref on a page which some other CPU has * already deemed to be freeable. * * NO code should make assumptions about this internal detail! Use the provided * macros which retain the old rules: page_count(page) == 0 is a free page. */ /* * Drop a ref, return true if the logical refcount fell to zero (the page has * no users) */ #define put_page_testzero(p) \ ({ \ BUG_ON(page_count(p) == 0); \ atomic_add_negative(-1, &(p)->_count); \ }) /* * Grab a ref, return true if the page previously had a logical refcount of * zero. ie: returns true if we just grabbed an already-deemed-to-be-free page */ #define get_page_testone(p) atomic_inc_and_test(&(p)->_count) #define set_page_count(p,v) atomic_set(&(p)->_count, v - 1) #define __put_page(p) atomic_dec(&(p)->_count) extern void FASTCALL(__page_cache_release(struct page *)); static inline int page_count(struct page *page) { if (PageCompound(page)) page = (struct page *)page_private(page); return atomic_read(&page->_count) + 1; } static inline void get_page(struct page *page) { if (unlikely(PageCompound(page))) page = (struct page *)page_private(page); atomic_inc(&page->_count); } void put_page(struct page *page); /* * Multiple processes may "see" the same page. E.g. for untouched * mappings of /dev/null, all processes see the same page full of * zeroes, and text pages of executables and shared libraries have * only one copy in memory, at most, normally. * * For the non-reserved pages, page_count(page) denotes a reference count. * page_count() == 0 means the page is free. page->lru is then used for * freelist management in the buddy allocator. * page_count() == 1 means the page is used for exactly one purpose * (e.g. a private data page of one process). * * A page may be used for kmalloc() or anyone else who does a * __get_free_page(). In this case the page_count() is at least 1, and * all other fields are unused but should be 0 or NULL. The * management of this page is the responsibility of the one who uses * it. * * The other pages (we may call them "process pages") are completely * managed by the Linux memory manager: I/O, buffers, swapping etc. * The following discussion applies only to them. * * A page may belong to an inode's memory mapping. In this case, * page->mapping is the pointer to the inode, and page->index is the * file offset of the page, in units of PAGE_CACHE_SIZE. * * A page contains an opaque `private' member, which belongs to the * page's address_space. Usually, this is the address of a circular * list of the page's disk buffers. * * For pages belonging to inodes, the page_count() is the number of * attaches, plus 1 if `private' contains something, plus one for * the page cache itself. * * Instead of keeping dirty/clean pages in per address-space lists, we instead * now tag pages as dirty/under writeback in the radix tree. * * There is also a per-mapping radix tree mapping index to the page * in memory if present. The tree is rooted at mapping->root. * * All process pages can do I/O: * - inode pages may need to be read from disk, * - inode pages which have been modified and are MAP_SHARED may need * to be written to disk, * - private pages which have been modified may need to be swapped out * to swap space and (later) to be read back into memory. */ /* * The zone field is never updated after free_area_init_core() * sets it, so none of the operations on it need to be atomic. */ /* * page->flags layout: * * There are three possibilities for how page->flags get * laid out. The first is for the normal case, without * sparsemem. The second is for sparsemem when there is * plenty of space for node and section. The last is when * we have run out of space and have to fall back to an * alternate (slower) way of determining the node. * * No sparsemem: | NODE | ZONE | ... | FLAGS | * with space for node: | SECTION | NODE | ZONE | ... | FLAGS | * no space for node: | SECTION | ZONE | ... | FLAGS | */ #ifdef CONFIG_SPARSEMEM #define SECTIONS_WIDTH SECTIONS_SHIFT #else #define SECTIONS_WIDTH 0 #endif #define ZONES_WIDTH ZONES_SHIFT #if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT <= FLAGS_RESERVED #define NODES_WIDTH NODES_SHIFT #else #define NODES_WIDTH 0 #endif /* Page flags: | [SECTION] | [NODE] | ZONE | ... | FLAGS | */ #define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH) #define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH) #define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH) /* * We are going to use the flags for the page to node mapping if its in * there. This includes the case where there is no node, so it is implicit. */ #define FLAGS_HAS_NODE (NODES_WIDTH > 0 || NODES_SHIFT == 0) #ifndef PFN_SECTION_SHIFT #define PFN_SECTION_SHIFT 0 #endif /* * Define the bit shifts to access each section. For non-existant * sections we define the shift as 0; that plus a 0 mask ensures * the compiler will optimise away reference to them. */ #define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0)) #define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0)) #define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0)) /* NODE:ZONE or SECTION:ZONE is used to lookup the zone from a page. */ #if FLAGS_HAS_NODE #define ZONETABLE_SHIFT (NODES_SHIFT + ZONES_SHIFT) #else #define ZONETABLE_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT) #endif #define ZONETABLE_PGSHIFT ZONES_PGSHIFT #if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > FLAGS_RESERVED #error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > FLAGS_RESERVED #endif #define ZONES_MASK ((1UL << ZONES_WIDTH) - 1) #define NODES_MASK ((1UL << NODES_WIDTH) - 1) #define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1) #define ZONETABLE_MASK ((1UL << ZONETABLE_SHIFT) - 1) static inline unsigned long page_zonenum(struct page *page) { return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK; } struct zone; extern struct zone *zone_table[]; static inline struct zone *page_zone(struct page *page) { return zone_table[(page->flags >> ZONETABLE_PGSHIFT) & ZONETABLE_MASK]; } static inline unsigned long page_to_nid(struct page *page) { if (FLAGS_HAS_NODE) return (page->flags >> NODES_PGSHIFT) & NODES_MASK; else return page_zone(page)->zone_pgdat->node_id; } static inline unsigned long page_to_section(struct page *page) { return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK; } static inline void set_page_zone(struct page *page, unsigned long zone) { page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT); page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT; } static inline void set_page_node(struct page *page, unsigned long node) { page->flags &= ~(NODES_MASK << NODES_PGSHIFT); page->flags |= (node & NODES_MASK) << NODES_PGSHIFT; } static inline void set_page_section(struct page *page, unsigned long section) { page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT); page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT; } static inline void set_page_links(struct page *page, unsigned long zone, unsigned long node, unsigned long pfn) { set_page_zone(page, zone); set_page_node(page, node); set_page_section(page, pfn_to_section_nr(pfn)); } #ifndef CONFIG_DISCONTIGMEM /* The array of struct pages - for discontigmem use pgdat->lmem_map */ extern struct page *mem_map; #endif static inline void *lowmem_page_address(struct page *page) { return __va(page_to_pfn(page) << PAGE_SHIFT); } #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) #define HASHED_PAGE_VIRTUAL #endif #if defined(WANT_PAGE_VIRTUAL) #define page_address(page) ((page)->virtual) #define set_page_address(page, address) \ do { \ (page)->virtual = (address); \ } while(0) #define page_address_init() do { } while(0) #endif #if defined(HASHED_PAGE_VIRTUAL) void *page_address(struct page *page); void set_page_address(struct page *page, void *virtual); void page_address_init(void); #endif #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL) #define page_address(page) lowmem_page_address(page) #define set_page_address(page, address) do { } while(0) #define page_address_init() do { } while(0) #endif /* * On an anonymous page mapped into a user virtual memory area, * page->mapping points to its anon_vma, not to a struct address_space; * with the PAGE_MAPPING_ANON bit set to distinguish it. * * Please note that, confusingly, "page_mapping" refers to the inode * address_space which maps the page from disk; whereas "page_mapped" * refers to user virtual address space into which the page is mapped. */ #define PAGE_MAPPING_ANON 1 extern struct address_space swapper_space; static inline struct address_space *page_mapping(struct page *page) { struct address_space *mapping = page->mapping; if (unlikely(PageSwapCache(page))) mapping = &swapper_space; else if (unlikely((unsigned long)mapping & PAGE_MAPPING_ANON)) mapping = NULL; return mapping; } static inline int PageAnon(struct page *page) { return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0; } /* * Return the pagecache index of the passed page. Regular pagecache pages * use ->index whereas swapcache pages use ->private */ static inline pgoff_t page_index(struct page *page) { if (unlikely(PageSwapCache(page))) return page_private(page); return page->index; } /* * The atomic page->_mapcount, like _count, starts from -1: * so that transitions both from it and to it can be tracked, * using atomic_inc_and_test and atomic_add_negative(-1). */ static inline void reset_page_mapcount(struct page *page) { atomic_set(&(page)->_mapcount, -1); } static inline int page_mapcount(struct page *page) { return atomic_read(&(page)->_mapcount) + 1; } /* * Return true if this page is mapped into pagetables. */ static inline int page_mapped(struct page *page) { return atomic_read(&(page)->_mapcount) >= 0; } /* * Error return values for the *_nopage functions */ #define NOPAGE_SIGBUS (NULL) #define NOPAGE_OOM ((struct page *) (-1)) /* * Different kinds of faults, as returned by handle_mm_fault(). * Used to decide whether a process gets delivered SIGBUS or * just gets major/minor fault counters bumped up. */ #define VM_FAULT_OOM 0x00 #define VM_FAULT_SIGBUS 0x01 #define VM_FAULT_MINOR 0x02 #define VM_FAULT_MAJOR 0x03 /* * Special case for get_user_pages. * Must be in a distinct bit from the above VM_FAULT_ flags. */ #define VM_FAULT_WRITE 0x10 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) extern void show_free_areas(void); #ifdef CONFIG_SHMEM struct page *shmem_nopage(struct vm_area_struct *vma, unsigned long address, int *type); int shmem_set_policy(struct vm_area_struct *vma, struct mempolicy *new); struct mempolicy *shmem_get_policy(struct vm_area_struct *vma, unsigned long addr); int shmem_lock(struct file *file, int lock, struct user_struct *user); #else #define shmem_nopage filemap_nopage #define shmem_lock(a, b, c) ({0;}) /* always in memory, no need to lock */ #define shmem_set_policy(a, b) (0) #define shmem_get_policy(a, b) (NULL) #endif struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags); int shmem_zero_setup(struct vm_area_struct *); static inline int can_do_mlock(void) { if (capable(CAP_IPC_LOCK)) return 1; if (current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur != 0) return 1; return 0; } extern int user_shm_lock(size_t, struct user_struct *); extern void user_shm_unlock(size_t, struct user_struct *); /* * Parameter block passed down to zap_pte_range in exceptional cases. */ struct zap_details { struct vm_area_struct *nonlinear_vma; /* Check page->index if set */ struct address_space *check_mapping; /* Check page->mapping if set */ pgoff_t first_index; /* Lowest page->index to unmap */ pgoff_t last_index; /* Highest page->index to unmap */ spinlock_t *i_mmap_lock; /* For unmap_mapping_range: */ unsigned long truncate_count; /* Compare vm_truncate_count */ }; struct page *vm_normal_page(struct vm_area_struct *, unsigned long, pte_t); unsigned long zap_page_range(struct vm_area_struct *vma, unsigned long address, unsigned long size, struct zap_details *); unsigned long unmap_vmas(struct mmu_gather **tlb, struct vm_area_struct *start_vma, unsigned long start_addr, unsigned long end_addr, unsigned long *nr_accounted, struct zap_details *); void free_pgd_range(struct mmu_gather **tlb, unsigned long addr, unsigned long end, unsigned long floor, unsigned long ceiling); void free_pgtables(struct mmu_gather **tlb, struct vm_area_struct *start_vma, unsigned long floor, unsigned long ceiling); int copy_page_range(struct mm_struct *dst, struct mm_struct *src, struct vm_area_struct *vma); int zeromap_page_range(struct vm_area_struct *vma, unsigned long from, unsigned long size, pgprot_t prot); void unmap_mapping_range(struct address_space *mapping, loff_t const holebegin, loff_t const holelen, int even_cows); static inline void unmap_shared_mapping_range(struct address_space *mapping, loff_t const holebegin, loff_t const holelen) { unmap_mapping_range(mapping, holebegin, holelen, 0); } extern int vmtruncate(struct inode * inode, loff_t offset); extern int install_page(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, struct page *page, pgprot_t prot); extern int install_file_pte(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, unsigned long pgoff, pgprot_t prot); extern int __handle_mm_fault(struct mm_struct *mm,struct vm_area_struct *vma, unsigned long address, int write_access); static inline int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, int write_access) { return __handle_mm_fault(mm, vma, address, write_access) & (~VM_FAULT_WRITE); } extern int make_pages_present(unsigned long addr, unsigned long end); extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write); void install_arg_page(struct vm_area_struct *, struct page *, unsigned long); int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, int len, int write, int force, struct page **pages, struct vm_area_struct **vmas); void print_bad_pte(struct vm_area_struct *, pte_t, unsigned long); int __set_page_dirty_buffers(struct page *page); int __set_page_dirty_nobuffers(struct page *page); int redirty_page_for_writepage(struct writeback_control *wbc, struct page *page); int FASTCALL(set_page_dirty(struct page *page)); int set_page_dirty_lock(struct page *page); int clear_page_dirty_for_io(struct page *page); extern unsigned long do_mremap(unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags, unsigned long new_addr); /* * Prototype to add a shrinker callback for ageable caches. * * These functions are passed a count `nr_to_scan' and a gfpmask. They should * scan `nr_to_scan' objects, attempting to free them. * * The callback must return the number of objects which remain in the cache. * * The callback will be passed nr_to_scan == 0 when the VM is querying the * cache size, so a fastpath for that case is appropriate. */ typedef int (*shrinker_t)(int nr_to_scan, gfp_t gfp_mask); /* * Add an aging callback. The int is the number of 'seeks' it takes * to recreate one of the objects that these functions age. */ #define DEFAULT_SEEKS 2 struct shrinker; extern struct shrinker *set_shrinker(int, shrinker_t); extern void remove_shrinker(struct shrinker *shrinker); int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address); int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address); int __pte_alloc_kernel(pmd_t *pmd, unsigned long address); /* * The following ifdef needed to get the 4level-fixup.h header to work. * Remove it when 4level-fixup.h has been removed. */ #if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK) static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address) { return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))? NULL: pud_offset(pgd, address); } static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) { return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))? NULL: pmd_offset(pud, address); } #endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */ #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS /* * We tuck a spinlock to guard each pagetable page into its struct page, * at page->private, with BUILD_BUG_ON to make sure that this will not * overflow into the next struct page (as it might with DEBUG_SPINLOCK). * When freeing, reset page->mapping so free_pages_check won't complain. */ #define __pte_lockptr(page) &((page)->u.ptl) #define pte_lock_init(_page) do { \ spin_lock_init(__pte_lockptr(_page)); \ } while (0) #define pte_lock_deinit(page) ((page)->mapping = NULL) #define pte_lockptr(mm, pmd) ({(void)(mm); __pte_lockptr(pmd_page(*(pmd)));}) #else /* * We use mm->page_table_lock to guard all pagetable pages of the mm. */ #define pte_lock_init(page) do {} while (0) #define pte_lock_deinit(page) do {} while (0) #define pte_lockptr(mm, pmd) ({(void)(pmd); &(mm)->page_table_lock;}) #endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */ #define pte_offset_map_lock(mm, pmd, address, ptlp) \ ({ \ spinlock_t *__ptl = pte_lockptr(mm, pmd); \ pte_t *__pte = pte_offset_map(pmd, address); \ *(ptlp) = __ptl; \ spin_lock(__ptl); \ __pte; \ }) #define pte_unmap_unlock(pte, ptl) do { \ spin_unlock(ptl); \ pte_unmap(pte); \ } while (0) #define pte_alloc_map(mm, pmd, address) \ ((unlikely(!pmd_present(*(pmd))) && __pte_alloc(mm, pmd, address))? \ NULL: pte_offset_map(pmd, address)) #define pte_alloc_map_lock(mm, pmd, address, ptlp) \ ((unlikely(!pmd_present(*(pmd))) && __pte_alloc(mm, pmd, address))? \ NULL: pte_offset_map_lock(mm, pmd, address, ptlp)) #define pte_alloc_kernel(pmd, address) \ ((unlikely(!pmd_present(*(pmd))) && __pte_alloc_kernel(pmd, address))? \ NULL: pte_offset_kernel(pmd, address)) extern void free_area_init(unsigned long * zones_size); extern void free_area_init_node(int nid, pg_data_t *pgdat, unsigned long * zones_size, unsigned long zone_start_pfn, unsigned long *zholes_size); extern void memmap_init_zone(unsigned long, int, unsigned long, unsigned long); extern void setup_per_zone_pages_min(void); extern void mem_init(void); extern void show_mem(void); extern void si_meminfo(struct sysinfo * val); extern void si_meminfo_node(struct sysinfo *val, int nid); #ifdef CONFIG_NUMA extern void setup_per_cpu_pageset(void); #else static inline void setup_per_cpu_pageset(void) {} #endif /* prio_tree.c */ void vma_prio_tree_add(struct vm_area_struct *, struct vm_area_struct *old); void vma_prio_tree_insert(struct vm_area_struct *, struct prio_tree_root *); void vma_prio_tree_remove(struct vm_area_struct *, struct prio_tree_root *); struct vm_area_struct *vma_prio_tree_next(struct vm_area_struct *vma, struct prio_tree_iter *iter); #define vma_prio_tree_foreach(vma, iter, root, begin, end) \ for (prio_tree_iter_init(iter, root, begin, end), vma = NULL; \ (vma = vma_prio_tree_next(vma, iter)); ) static inline void vma_nonlinear_insert(struct vm_area_struct *vma, struct list_head *list) { vma->shared.vm_set.parent = NULL; list_add_tail(&vma->shared.vm_set.list, list); } /* mmap.c */ extern int __vm_enough_memory(long pages, int cap_sys_admin); extern void vma_adjust(struct vm_area_struct *vma, unsigned long start, unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert); extern struct vm_area_struct *vma_merge(struct mm_struct *, struct vm_area_struct *prev, unsigned long addr, unsigned long end, unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t, struct mempolicy *); extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *); extern int split_vma(struct mm_struct *, struct vm_area_struct *, unsigned long addr, int new_below); extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *); extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *, struct rb_node **, struct rb_node *); extern void unlink_file_vma(struct vm_area_struct *); extern struct vm_area_struct *copy_vma(struct vm_area_struct **, unsigned long addr, unsigned long len, pgoff_t pgoff); extern void exit_mmap(struct mm_struct *); extern int may_expand_vm(struct mm_struct *mm, unsigned long npages); extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, unsigned long len, unsigned long prot, unsigned long flag, unsigned long pgoff); static inline unsigned long do_mmap(struct file *file, unsigned long addr, unsigned long len, unsigned long prot, unsigned long flag, unsigned long offset) { unsigned long ret = -EINVAL; if ((offset + PAGE_ALIGN(len)) < offset) goto out; if (!(offset & ~PAGE_MASK)) ret = do_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT); out: return ret; } extern int do_munmap(struct mm_struct *, unsigned long, size_t); extern unsigned long do_brk(unsigned long, unsigned long); /* filemap.c */ extern unsigned long page_unuse(struct page *); extern void truncate_inode_pages(struct address_space *, loff_t); /* generic vm_area_ops exported for stackable file systems */ extern struct page *filemap_nopage(struct vm_area_struct *, unsigned long, int *); extern int filemap_populate(struct vm_area_struct *, unsigned long, unsigned long, pgprot_t, unsigned long, int); /* mm/page-writeback.c */ int write_one_page(struct page *page, int wait); /* readahead.c */ #define VM_MAX_READAHEAD 128 /* kbytes */ #define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */ #define VM_MAX_CACHE_HIT 256 /* max pages in a row in cache before * turning readahead off */ int do_page_cache_readahead(struct address_space *mapping, struct file *filp, pgoff_t offset, unsigned long nr_to_read); int force_page_cache_readahead(struct address_space *mapping, struct file *filp, pgoff_t offset, unsigned long nr_to_read); unsigned long page_cache_readahead(struct address_space *mapping, struct file_ra_state *ra, struct file *filp, pgoff_t offset, unsigned long size); void handle_ra_miss(struct address_space *mapping, struct file_ra_state *ra, pgoff_t offset); unsigned long max_sane_readahead(unsigned long nr); /* Do stack extension */ extern int expand_stack(struct vm_area_struct *vma, unsigned long address); #ifdef CONFIG_IA64 extern int expand_upwards(struct vm_area_struct *vma, unsigned long address); #endif /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */ extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr); extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr, struct vm_area_struct **pprev); /* Look up the first VMA which intersects the interval start_addr..end_addr-1, NULL if none. Assume start_addr < end_addr. */ static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr) { struct vm_area_struct * vma = find_vma(mm,start_addr); if (vma && end_addr <= vma->vm_start) vma = NULL; return vma; } static inline unsigned long vma_pages(struct vm_area_struct *vma) { return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; } struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr); struct page *vmalloc_to_page(void *addr); unsigned long vmalloc_to_pfn(void *addr); int remap_pfn_range(struct vm_area_struct *, unsigned long addr, unsigned long pfn, unsigned long size, pgprot_t); struct page *follow_page(struct vm_area_struct *, unsigned long address, unsigned int foll_flags); #define FOLL_WRITE 0x01 /* check pte is writable */ #define FOLL_TOUCH 0x02 /* mark page accessed */ #define FOLL_GET 0x04 /* do get_page on page */ #define FOLL_ANON 0x08 /* give ZERO_PAGE if no pgtable */ #ifdef CONFIG_PROC_FS void vm_stat_account(struct mm_struct *, unsigned long, struct file *, long); #else static inline void vm_stat_account(struct mm_struct *mm, unsigned long flags, struct file *file, long pages) { } #endif /* CONFIG_PROC_FS */ #ifndef CONFIG_DEBUG_PAGEALLOC static inline void kernel_map_pages(struct page *page, int numpages, int enable) { } #endif extern struct vm_area_struct *get_gate_vma(struct task_struct *tsk); #ifdef __HAVE_ARCH_GATE_AREA int in_gate_area_no_task(unsigned long addr); int in_gate_area(struct task_struct *task, unsigned long addr); #else int in_gate_area_no_task(unsigned long addr); #define in_gate_area(task, addr) ({(void)task; in_gate_area_no_task(addr);}) #endif /* __HAVE_ARCH_GATE_AREA */ /* /proc//oom_adj set to -17 protects from the oom-killer */ #define OOM_DISABLE -17 #endif /* __KERNEL__ */ #endif /* _LINUX_MM_H */