X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Flinux%2Fmm.h;h=27f8de8eaf7d4bc7ace06d4b0a35303877df4ae1;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=5c584ccededa50f83d0228ae2799e3941db7e57e;hpb=9bf4aaab3e101692164d49b7ca357651eb691cb6;p=linux-2.6.git diff --git a/include/linux/mm.h b/include/linux/mm.h index 5c584cced..27f8de8ea 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3,16 +3,20 @@ #include #include +#include #ifdef __KERNEL__ -#include #include #include #include #include #include #include +#include +#include +#include +#include struct mempolicy; struct anon_vma; @@ -26,14 +30,17 @@ 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 -#ifndef MM_VM_SIZE -#define MM_VM_SIZE(mm) TASK_SIZE -#endif +#define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n)) /* * Linux kernel virtual memory manager primitives. @@ -77,7 +84,7 @@ struct vm_area_struct { struct vm_area_struct *head; } vm_set; - struct prio_tree_node prio_tree_node; + struct raw_prio_tree_node prio_tree_node; } shared; /* @@ -97,12 +104,35 @@ struct vm_area_struct { 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 }; +extern struct kmem_cache *vm_area_cachep; + +/* + * 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.. */ @@ -111,6 +141,7 @@ struct vm_area_struct { #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 @@ -118,7 +149,7 @@ struct vm_area_struct { #define VM_GROWSDOWN 0x00000100 /* general info on the segment */ #define VM_GROWSUP 0x00000200 -#define VM_SHM 0x00000400 /* shared memory area, don't swap out */ +#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 @@ -131,10 +162,16 @@ struct vm_area_struct { #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ -#define VM_RESERVED 0x00080000 /* Don't unmap it from swap_out */ +#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_INSERTPAGE 0x02000000 /* The vma has had "vm_insert_page()" done on it */ +#define VM_ALWAYSDUMP 0x04000000 /* Always include in core dumps */ +#ifdef CONFIG_XEN +#define VM_FOREIGN 0x08000000 /* Has pages belonging to another VM */ +#endif #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */ #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS @@ -168,68 +205,26 @@ 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); + unsigned long (*nopfn)(struct vm_area_struct * area, unsigned long address); int (*populate)(struct vm_area_struct * area, unsigned long address, unsigned long len, pgprot_t prot, unsigned long pgoff, int nonblock); + + /* notification that a previously read-only page is about to become + * writable, if an error is returned it will cause a SIGBUS */ + int (*page_mkwrite)(struct vm_area_struct *vma, struct page *page); #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); + int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from, + const nodemask_t *to, unsigned long flags); #endif }; struct mmu_gather; struct inode; -#ifdef ARCH_HAS_ATOMIC_UNSIGNED -typedef unsigned page_flags_t; -#else -typedef unsigned long page_flags_t; -#endif - -/* - * 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 { - page_flags_t flags; /* Atomic flags, some possibly - * updated asynchronously */ - atomic_t _count; /* Usage count, see below. */ - unsigned int mapcount; /* Count of ptes mapped in mms, - * to show when page is mapped - * & limit reverse map searches, - * protected by PG_maplock. - */ - unsigned long private; /* Mapping-private opaque data: - * usually used for buffer_heads - * if PagePrivate set; used for - * swp_entry_t if PageSwapCache - */ - struct address_space *mapping; /* If PG_anon clear, points to - * inode address_space, or NULL. - * If page mapped as anonymous - * memory, PG_anon is set, and - * it points to anon_vma object. - */ - 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)->private) +#define set_page_private(page, v) ((page)->private = (v)) /* * FIXME: take this include out, include page-flags.h in @@ -237,6 +232,12 @@ struct page { */ #include +#ifdef CONFIG_DEBUG_VM +#define VM_BUG_ON(cond) BUG_ON(cond) +#else +#define VM_BUG_ON(condition) do { } while(0) +#endif + /* * Methods to modify the page usage count. * @@ -248,73 +249,74 @@ struct page { * * 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) + * Drop a ref, return true if the 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); \ - }) +static inline int put_page_testzero(struct page *page) +{ + VM_BUG_ON(atomic_read(&page->_count) == 0); + return atomic_dec_and_test(&page->_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 + * Try to grab a ref unless the page has a refcount of zero, return false if + * that is the case. */ -#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 *)); - -#ifdef CONFIG_HUGETLB_PAGE +static inline int get_page_unless_zero(struct page *page) +{ + VM_BUG_ON(PageCompound(page)); + return atomic_inc_not_zero(&page->_count); +} -static inline int page_count(struct page *p) +static inline int page_count(struct page *page) { - if (PageCompound(p)) - p = (struct page *)p->private; - return atomic_read(&(p)->_count) + 1; + if (unlikely(PageCompound(page))) + page = (struct page *)page_private(page); + return atomic_read(&page->_count); } static inline void get_page(struct page *page) { if (unlikely(PageCompound(page))) - page = (struct page *)page->private; + page = (struct page *)page_private(page); + VM_BUG_ON(atomic_read(&page->_count) == 0); atomic_inc(&page->_count); } +/* + * Setup the page count before being freed into the page allocator for + * the first time (boot or memory hotplug) + */ +static inline void init_page_count(struct page *page) +{ + atomic_set(&page->_count, 1); +} + void put_page(struct page *page); +void put_pages_list(struct list_head *pages); -#else /* CONFIG_HUGETLB_PAGE */ +void split_page(struct page *page, unsigned int order); -#define page_count(p) (atomic_read(&(p)->_count) + 1) +/* + * Compound pages have a destructor function. Provide a + * prototype for that function and accessor functions. + * These are _only_ valid on the head of a PG_compound page. + */ +typedef void compound_page_dtor(struct page *); -static inline void get_page(struct page *page) +static inline void set_compound_page_dtor(struct page *page, + compound_page_dtor *dtor) { - atomic_inc(&page->_count); + page[1].lru.next = (void *)dtor; } -static inline void put_page(struct page *page) +static inline compound_page_dtor *get_compound_page_dtor(struct page *page) { - if (!PageReserved(page) && put_page_testzero(page)) - __page_cache_release(page); + return (compound_page_dtor *)page[1].lru.next; } -#endif /* CONFIG_HUGETLB_PAGE */ - /* * Multiple processes may "see" the same page. E.g. for untouched * mappings of /dev/null, all processes see the same page full of @@ -322,86 +324,220 @@ static inline void put_page(struct page *page) * 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_count() == 1 means the page is used for exactly one purpose - * (e.g. a private data page of one process). + * page_count() == 0 means the page is free. page->lru is then used for + * freelist management in the buddy allocator. + * page_count() > 0 means the page has been allocated. + * + * Pages are allocated by the slab allocator in order to provide memory + * to kmalloc and kmem_cache_alloc. In this case, the management of the + * page, and the fields in 'struct page' are the responsibility of mm/slab.c + * unless a particular usage is carefully commented. (the responsibility of + * freeing the kmalloc memory is the caller's, of course). * - * 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. + * A page may be used by anyone else who does a __get_free_page(). + * In this case, page_count still tracks the references, and should only + * be used through the normal accessor functions. The top bits of page->flags + * and page->virtual store page management information, but all other fields + * are unused and could be used privately, carefully. The management of this + * page is the responsibility of the one who allocated it, and those who have + * subsequently been given references to it. * - * The other pages (we may call them "process pages") are completely + * The other pages (we may call them "pagecache 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 pagecache 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. PG_private must be set to tell the VM to call + * into the filesystem to release these pages. * - * 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. + * 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. * - * 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. + * If pagecache pages are not associated with an inode, they are said to be + * anonymous pages. These may become associated with the swapcache, and in that + * case PG_swapcache is set, and page->private is an offset into the swapcache. * - * All pages belonging to an inode are in these doubly linked lists: - * mapping->clean_pages, mapping->dirty_pages and mapping->locked_pages; - * using the page->list list_head. These fields are also used for - * freelist managemet (when page_count()==0). + * In either case (swapcache or inode backed), the pagecache itself holds one + * reference to the page. Setting PG_private should also increment the + * refcount. The each user mapping also has a reference to the page. * - * There is also a per-mapping radix tree mapping index to the page - * in memory if present. The tree is rooted at mapping->root. + * The pagecache pages are stored in a per-mapping radix tree, which is + * rooted at mapping->page_tree, and indexed by offset. + * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space + * lists, we instead now tag pages as dirty/writeback in the radix tree. * - * All process pages can do I/O: + * All pagecache pages may be subject to 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. + * to be written back to the inode on disk, + * - anonymous pages (including MAP_PRIVATE file mappings) 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. - * We'll have up to (MAX_NUMNODES * MAX_NR_ZONES) zones total, - * so we use (MAX_NODES_SHIFT + MAX_ZONES_SHIFT) here to get enough bits. */ -#define NODEZONE_SHIFT (sizeof(page_flags_t)*8 - MAX_NODES_SHIFT - MAX_ZONES_SHIFT) -#define NODEZONE(node, zone) ((node << ZONES_SHIFT) | zone) -static inline unsigned long page_zonenum(struct page *page) + +/* + * 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. + */ +#if !(NODES_WIDTH > 0 || NODES_SHIFT == 0) +#define NODE_NOT_IN_PAGE_FLAGS +#endif + +#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 ID a zone for the buddy allcator */ +#ifdef NODE_NOT_IN_PAGEFLAGS +#define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT) +#else +#define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT) +#endif + +#if ZONES_WIDTH > 0 +#define ZONEID_PGSHIFT ZONES_PGSHIFT +#else +#define ZONEID_PGSHIFT NODES_PGOFF +#endif + +#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 ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1) + +static inline enum zone_type page_zonenum(struct page *page) { - return (page->flags >> NODEZONE_SHIFT) & (~(~0UL << ZONES_SHIFT)); + return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK; } -static inline unsigned long page_to_nid(struct page *page) + +/* + * The identification function is only used by the buddy allocator for + * determining if two pages could be buddies. We are not really + * identifying a zone since we could be using a the section number + * id if we have not node id available in page flags. + * We guarantee only that it will return the same value for two + * combinable pages in a zone. + */ +static inline int page_zone_id(struct page *page) { - return (page->flags >> (NODEZONE_SHIFT + ZONES_SHIFT)); + BUILD_BUG_ON(ZONEID_PGSHIFT == 0 && ZONEID_MASK); + return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK; } -struct zone; -extern struct zone *zone_table[]; +static inline int zone_to_nid(struct zone *zone) +{ +#ifdef CONFIG_NUMA + return zone->node; +#else + return 0; +#endif +} + +#ifdef NODE_NOT_IN_PAGE_FLAGS +extern int page_to_nid(struct page *page); +#else +static inline int page_to_nid(struct page *page) +{ + return (page->flags >> NODES_PGSHIFT) & NODES_MASK; +} +#endif static inline struct zone *page_zone(struct page *page) { - return zone_table[page->flags >> NODEZONE_SHIFT]; + return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)]; } -static inline void set_page_zone(struct page *page, unsigned long nodezone_num) +static inline unsigned long page_to_section(struct page *page) { - page->flags &= ~(~0UL << NODEZONE_SHIFT); - page->flags |= nodezone_num << NODEZONE_SHIFT; + return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK; } -#ifndef CONFIG_DISCONTIGMEM -/* The array of struct pages - for discontigmem use pgdat->lmem_map */ -extern struct page *mem_map; -#endif +static inline void set_page_zone(struct page *page, enum zone_type 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, enum zone_type 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)); +} -static inline void *lowmem_page_address(struct page *page) +/* + * Some inline functions in vmstat.h depend on page_zone() + */ +#include + +static __always_inline void *lowmem_page_address(struct page *page) { return __va(page_to_pfn(page) << PAGE_SHIFT); } @@ -433,24 +569,32 @@ void page_address_init(void); /* * On an anonymous page mapped into a user virtual memory area, - * page->mapping points to its anon_vma, not to a struct address_space. + * 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 = NULL; + struct address_space *mapping = page->mapping; if (unlikely(PageSwapCache(page))) mapping = &swapper_space; - else if (likely(!PageAnon(page))) - mapping = page->mapping; + 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 @@ -458,16 +602,31 @@ static inline struct address_space *page_mapping(struct page *page) static inline pgoff_t page_index(struct page *page) { if (unlikely(PageSwapCache(page))) - return page->private; + 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 page->mapcount != 0; + return atomic_read(&(page)->_mapcount) >= 0; } /* @@ -475,30 +634,86 @@ static inline int page_mapped(struct page *page) */ #define NOPAGE_SIGBUS (NULL) #define NOPAGE_OOM ((struct page *) (-1)) +#define NOPAGE_REFAULT ((struct page *) (-2)) /* Return to userspace, rerun */ + +/* + * Error return values for the *_nopfn functions + */ +#define NOPFN_SIGBUS ((unsigned long) -1) +#define NOPFN_OOM ((unsigned long) -2) /* * 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 (-1) -#define VM_FAULT_SIGBUS 0 -#define VM_FAULT_MINOR 1 -#define VM_FAULT_MAJOR 2 +#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); -struct page *shmem_nopage(struct vm_area_struct * vma, +#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); -struct file *shmem_file_setup(char * name, loff_t size, unsigned long flags); -void shmem_lock(struct file * file, int lock); +int shmem_lock(struct file *file, int lock, struct user_struct *user); +#else +#define shmem_nopage filemap_nopage + +static inline int shmem_lock(struct file *file, int lock, + struct user_struct *user) +{ + return 0; +} + +static inline int shmem_set_policy(struct vm_area_struct *vma, + struct mempolicy *new) +{ + return 0; +} + +static inline struct mempolicy *shmem_get_policy(struct vm_area_struct *vma, + unsigned long addr) +{ + return NULL; +} +#endif +struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags); +extern int shmem_mmap(struct file *file, struct vm_area_struct *vma); + int shmem_zero_setup(struct vm_area_struct *); +#ifndef CONFIG_MMU +extern unsigned long shmem_get_unmapped_area(struct file *file, + unsigned long addr, + unsigned long len, + unsigned long pgoff, + unsigned long flags); +#endif + +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. */ @@ -507,16 +722,21 @@ struct zap_details { 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 */ - int atomic; /* May not schedule() */ + spinlock_t *i_mmap_lock; /* For unmap_mapping_range: */ + unsigned long truncate_count; /* Compare vm_truncate_count */ }; -void zap_page_range(struct vm_area_struct *vma, unsigned long address, +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 *); -int unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm, +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 clear_page_tables(struct mmu_gather *tlb, unsigned long first, int nr); +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, @@ -531,20 +751,43 @@ static inline void unmap_shared_mapping_range(struct address_space *mapping, } extern int vmtruncate(struct inode * inode, loff_t offset); -extern pmd_t *FASTCALL(__pmd_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)); -extern pte_t *FASTCALL(pte_alloc_kernel(struct mm_struct *mm, pmd_t *pmd, unsigned long address)); -extern pte_t *FASTCALL(pte_alloc_map(struct mm_struct *mm, pmd_t *pmd, unsigned long address)); +extern int vmtruncate_range(struct inode * inode, loff_t offset, loff_t end); 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); + +#ifdef CONFIG_MMU +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); +} +#else +static inline int handle_mm_fault(struct mm_struct *mm, + struct vm_area_struct *vma, unsigned long address, + int write_access) +{ + /* should never happen if there's no MMU */ + BUG(); + return VM_FAULT_SIGBUS; +} +#endif + 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); + +extern int try_to_release_page(struct page * page, gfp_t gfp_mask); +extern void do_invalidatepage(struct page *page, unsigned long offset); -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); @@ -552,18 +795,22 @@ 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 the number of objects which remain in the cache. + * The callback must return the number of objects which remain in the cache. * - * The callback will be passes nr_to_scan == 0 when the VM is querying the + * 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, unsigned int gfp_mask); +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 @@ -576,45 +823,199 @@ extern struct shrinker *set_shrinker(int, shrinker_t); extern void remove_shrinker(struct shrinker *shrinker); /* - * On a two-level page table, this ends up being trivial. Thus the - * inlining and the symmetry break with pte_alloc_map() that does all - * of this out-of-line. + * Some shared mappigns will want the pages marked read-only + * to track write events. If so, we'll downgrade vm_page_prot + * to the private version (using protection_map[] without the + * VM_SHARED bit). */ -static inline pmd_t *pmd_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address) +static inline int vma_wants_writenotify(struct vm_area_struct *vma) { - if (pgd_none(*pgd)) - return __pmd_alloc(mm, pgd, address); - return pmd_offset(pgd, address); + unsigned int vm_flags = vma->vm_flags; + + /* If it was private or non-writable, the write bit is already clear */ + if ((vm_flags & (VM_WRITE|VM_SHARED)) != ((VM_WRITE|VM_SHARED))) + return 0; + + /* The backer wishes to know when pages are first written to? */ + if (vma->vm_ops && vma->vm_ops->page_mkwrite) + return 1; + + /* The open routine did something to the protections already? */ + if (pgprot_val(vma->vm_page_prot) != + pgprot_val(protection_map[vm_flags & + (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)])) + return 0; + + /* Specialty mapping? */ + if (vm_flags & (VM_PFNMAP|VM_INSERTPAGE)) + return 0; + + /* Can the mapping track the dirty pages? */ + return vma->vm_file && vma->vm_file->f_mapping && + mapping_cap_account_dirty(vma->vm_file->f_mapping); +} + +extern pte_t *FASTCALL(get_locked_pte(struct mm_struct *mm, unsigned long addr, spinlock_t **ptl)); + +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)->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, struct page *pmap, +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(struct page *, unsigned long, int, - unsigned long, unsigned long); +#ifdef CONFIG_ARCH_POPULATES_NODE_MAP +/* + * With CONFIG_ARCH_POPULATES_NODE_MAP set, an architecture may initialise its + * zones, allocate the backing mem_map and account for memory holes in a more + * architecture independent manner. This is a substitute for creating the + * zone_sizes[] and zholes_size[] arrays and passing them to + * free_area_init_node() + * + * An architecture is expected to register range of page frames backed by + * physical memory with add_active_range() before calling + * free_area_init_nodes() passing in the PFN each zone ends at. At a basic + * usage, an architecture is expected to do something like + * + * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn, + * max_highmem_pfn}; + * for_each_valid_physical_page_range() + * add_active_range(node_id, start_pfn, end_pfn) + * free_area_init_nodes(max_zone_pfns); + * + * If the architecture guarantees that there are no holes in the ranges + * registered with add_active_range(), free_bootmem_active_regions() + * will call free_bootmem_node() for each registered physical page range. + * Similarly sparse_memory_present_with_active_regions() calls + * memory_present() for each range when SPARSEMEM is enabled. + * + * See mm/page_alloc.c for more information on each function exposed by + * CONFIG_ARCH_POPULATES_NODE_MAP + */ +extern void free_area_init_nodes(unsigned long *max_zone_pfn); +extern void add_active_range(unsigned int nid, unsigned long start_pfn, + unsigned long end_pfn); +extern void shrink_active_range(unsigned int nid, unsigned long old_end_pfn, + unsigned long new_end_pfn); +extern void push_node_boundaries(unsigned int nid, unsigned long start_pfn, + unsigned long end_pfn); +extern void remove_all_active_ranges(void); +extern unsigned long absent_pages_in_range(unsigned long start_pfn, + unsigned long end_pfn); +extern void get_pfn_range_for_nid(unsigned int nid, + unsigned long *start_pfn, unsigned long *end_pfn); +extern unsigned long find_min_pfn_with_active_regions(void); +extern unsigned long find_max_pfn_with_active_regions(void); +extern void free_bootmem_with_active_regions(int nid, + unsigned long max_low_pfn); +extern void sparse_memory_present_with_active_regions(int nid); +#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID +extern int early_pfn_to_nid(unsigned long pfn); +#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */ +#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ +extern void set_dma_reserve(unsigned long new_dma_reserve); +extern void memmap_init_zone(unsigned long, int, unsigned long, + unsigned long, enum memmap_context); +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); -static inline void vma_prio_tree_init(struct vm_area_struct *vma) -{ - vma->shared.vm_set.list.next = NULL; - vma->shared.vm_set.list.prev = NULL; - vma->shared.vm_set.parent = NULL; - vma->shared.vm_set.head = NULL; -} +#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 *, struct prio_tree_root *, - struct prio_tree_iter *, pgoff_t begin, pgoff_t end); +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 *, @@ -624,14 +1025,23 @@ extern struct vm_area_struct *vma_merge(struct mm_struct *, 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 void insert_vm_struct(struct mm_struct *, struct vm_area_struct *); +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_prot(struct file *, unsigned long, unsigned long, unsigned long, unsigned long, int); -extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); + +static inline unsigned long get_unmapped_area(struct file * file, unsigned long addr, + unsigned long len, unsigned long pgoff, unsigned long flags) +{ + return get_unmapped_area_prot(file, addr, len, pgoff, flags, 0); +} extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, unsigned long len, unsigned long prot, @@ -657,9 +1067,13 @@ 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); +extern void truncate_inode_pages_range(struct address_space *, + loff_t lstart, loff_t lend); /* generic vm_area_ops exported for stackable file systems */ -struct page *filemap_nopage(struct vm_area_struct *, unsigned long, int *); +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); @@ -667,21 +1081,27 @@ 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, - unsigned long offset, unsigned long nr_to_read); + pgoff_t offset, unsigned long nr_to_read); int force_page_cache_readahead(struct address_space *mapping, struct file *filp, - unsigned long offset, unsigned long nr_to_read); -void page_cache_readahead(struct address_space *mapping, + 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, - unsigned long offset); -void handle_ra_miss(struct address_space *mapping, + 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); +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); @@ -704,25 +1124,65 @@ static inline unsigned long vma_pages(struct vm_area_struct *vma) return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; } -extern struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr); +pgprot_t vm_get_page_prot(unsigned long vm_flags); +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); +int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *); + +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_XEN +typedef int (*pte_fn_t)(pte_t *pte, struct page *pmd_page, unsigned long addr, + void *data); +extern int apply_to_page_range(struct mm_struct *mm, unsigned long address, + unsigned long size, pte_fn_t fn, void *data); +#endif -extern struct page * vmalloc_to_page(void *addr); -extern struct page * follow_page(struct mm_struct *mm, unsigned long address, - int write); -extern int remap_page_range(struct vm_area_struct *vma, unsigned long from, - unsigned long to, unsigned long size, pgprot_t prot); +#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) -{ -} +kernel_map_pages(struct page *page, int numpages, int enable) {} #endif -#ifndef CONFIG_ARCH_GATE_AREA 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 */ + +int drop_caches_sysctl_handler(struct ctl_table *, int, struct file *, + void __user *, size_t *, loff_t *); +unsigned long shrink_slab(unsigned long scanned, gfp_t gfp_mask, + unsigned long lru_pages); +void drop_pagecache(void); +void drop_slab(void); + +#ifndef CONFIG_MMU +#define randomize_va_space 0 +#else +extern int randomize_va_space; #endif +__attribute__((weak)) const char *arch_vma_name(struct vm_area_struct *vma); + #endif /* __KERNEL__ */ #endif /* _LINUX_MM_H */