Staging
v0.5.2
v0.5.2
https://github.com/torvalds/linux
Tip revision: 929096fe9ff1f4b3645cf3919527ab47e8d5e17c authored by Linus Torvalds on 19 December 2008, 01:20:13 UTC
Linux 2.6.28-rc9
Linux 2.6.28-rc9
Tip revision: 929096f
mm.h
#ifndef _LINUX_MM_H
#define _LINUX_MM_H
#include <linux/errno.h>
#ifdef __KERNEL__
#include <linux/gfp.h>
#include <linux/list.h>
#include <linux/mmdebug.h>
#include <linux/mmzone.h>
#include <linux/rbtree.h>
#include <linux/prio_tree.h>
#include <linux/debug_locks.h>
#include <linux/mm_types.h>
struct mempolicy;
struct anon_vma;
struct file_ra_state;
struct user_struct;
struct writeback_control;
#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 int page_cluster;
#ifdef CONFIG_SYSCTL
extern int sysctl_legacy_va_layout;
#else
#define sysctl_legacy_va_layout 0
#endif
extern unsigned long mmap_min_addr;
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
/* to align the pointer to the (next) page boundary */
#define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
/*
* 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).
*/
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 in vm_area_struct, see mm_types.h.
*/
#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_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_NORESERVE 0x00200000 /* should the VM suppress accounting */
#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 */
#define VM_CAN_NONLINEAR 0x08000000 /* Has ->fault & does nonlinear pages */
#define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */
#define VM_SAO 0x20000000 /* Strong Access Ordering (powerpc) */
#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)
/*
* special vmas that are non-mergable, non-mlock()able
*/
#define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_RESERVED | VM_PFNMAP)
/*
* mapping from the currently active vm_flags protection bits (the
* low four bits) to a page protection mask..
*/
extern pgprot_t protection_map[16];
#define FAULT_FLAG_WRITE 0x01 /* Fault was a write access */
#define FAULT_FLAG_NONLINEAR 0x02 /* Fault was via a nonlinear mapping */
/*
* vm_fault is filled by the the pagefault handler and passed to the vma's
* ->fault function. The vma's ->fault is responsible for returning a bitmask
* of VM_FAULT_xxx flags that give details about how the fault was handled.
*
* pgoff should be used in favour of virtual_address, if possible. If pgoff
* is used, one may set VM_CAN_NONLINEAR in the vma->vm_flags to get nonlinear
* mapping support.
*/
struct vm_fault {
unsigned int flags; /* FAULT_FLAG_xxx flags */
pgoff_t pgoff; /* Logical page offset based on vma */
void __user *virtual_address; /* Faulting virtual address */
struct page *page; /* ->fault handlers should return a
* page here, unless VM_FAULT_NOPAGE
* is set (which is also implied by
* VM_FAULT_ERROR).
*/
};
/*
* 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);
int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf);
/* 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);
/* called by access_process_vm when get_user_pages() fails, typically
* for use by special VMAs that can switch between memory and hardware
*/
int (*access)(struct vm_area_struct *vma, unsigned long addr,
void *buf, int len, int write);
#ifdef CONFIG_NUMA
/*
* set_policy() op must add a reference to any non-NULL @new mempolicy
* to hold the policy upon return. Caller should pass NULL @new to
* remove a policy and fall back to surrounding context--i.e. do not
* install a MPOL_DEFAULT policy, nor the task or system default
* mempolicy.
*/
int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
/*
* get_policy() op must add reference [mpol_get()] to any policy at
* (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure
* in mm/mempolicy.c will do this automatically.
* get_policy() must NOT add a ref if the policy at (vma,addr) is not
* marked as MPOL_SHARED. vma policies are protected by the mmap_sem.
* If no [shared/vma] mempolicy exists at the addr, get_policy() op
* must return NULL--i.e., do not "fallback" to task or system default
* policy.
*/
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;
#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
* files which need it (119 of them)
*/
#include <linux/page-flags.h>
/*
* 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.
*/
/*
* Drop a ref, return true if the refcount fell to zero (the page has no users)
*/
static inline int put_page_testzero(struct page *page)
{
VM_BUG_ON(atomic_read(&page->_count) == 0);
return atomic_dec_and_test(&page->_count);
}
/*
* Try to grab a ref unless the page has a refcount of zero, return false if
* that is the case.
*/
static inline int get_page_unless_zero(struct page *page)
{
VM_BUG_ON(PageTail(page));
return atomic_inc_not_zero(&page->_count);
}
/* Support for virtually mapped pages */
struct page *vmalloc_to_page(const void *addr);
unsigned long vmalloc_to_pfn(const void *addr);
/*
* Determine if an address is within the vmalloc range
*
* On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
* is no special casing required.
*/
static inline int is_vmalloc_addr(const void *x)
{
#ifdef CONFIG_MMU
unsigned long addr = (unsigned long)x;
return addr >= VMALLOC_START && addr < VMALLOC_END;
#else
return 0;
#endif
}
static inline struct page *compound_head(struct page *page)
{
if (unlikely(PageTail(page)))
return page->first_page;
return page;
}
static inline int page_count(struct page *page)
{
return atomic_read(&compound_head(page)->_count);
}
static inline void get_page(struct page *page)
{
page = compound_head(page);
VM_BUG_ON(atomic_read(&page->_count) == 0);
atomic_inc(&page->_count);
}
static inline struct page *virt_to_head_page(const void *x)
{
struct page *page = virt_to_page(x);
return compound_head(page);
}
/*
* 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);
void split_page(struct page *page, unsigned int order);
/*
* 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 set_compound_page_dtor(struct page *page,
compound_page_dtor *dtor)
{
page[1].lru.next = (void *)dtor;
}
static inline compound_page_dtor *get_compound_page_dtor(struct page *page)
{
return (compound_page_dtor *)page[1].lru.next;
}
static inline int compound_order(struct page *page)
{
if (!PageHead(page))
return 0;
return (unsigned long)page[1].lru.prev;
}
static inline void set_compound_order(struct page *page, unsigned long order)
{
page[1].lru.prev = (void *)order;
}
/*
* 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() > 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 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 "pagecache pages") are completely
* managed by the Linux memory manager: I/O, buffers, swapping etc.
* The following discussion applies only to them.
*
* 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 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.
*
* 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.
*
* 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.
*
* 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 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 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.
*/
/*
* 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 or sparsemem vmemmap: | NODE | ZONE | ... | FLAGS |
* classic sparse with space for node:| SECTION | NODE | ZONE | ... | FLAGS |
* classic sparse no space for node: | SECTION | ZONE | ... | FLAGS |
*/
#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
#define SECTIONS_WIDTH SECTIONS_SHIFT
#else
#define SECTIONS_WIDTH 0
#endif
#define ZONES_WIDTH ZONES_SHIFT
#if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT <= BITS_PER_LONG - NR_PAGEFLAGS
#define NODES_WIDTH NODES_SHIFT
#else
#ifdef CONFIG_SPARSEMEM_VMEMMAP
#error "Vmemmap: No space for nodes field in page flags"
#endif
#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)
#define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF)? \
SECTIONS_PGOFF : ZONES_PGOFF)
#else
#define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT)
#define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF)? \
NODES_PGOFF : ZONES_PGOFF)
#endif
#define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0))
#if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
#error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
#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 >> ZONES_PGSHIFT) & ZONES_MASK;
}
/*
* 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 >> ZONEID_PGSHIFT) & ZONEID_MASK;
}
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 &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
}
#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
static inline unsigned long page_to_section(struct page *page)
{
return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
}
#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));
}
/*
* If a hint addr is less than mmap_min_addr change hint to be as
* low as possible but still greater than mmap_min_addr
*/
static inline unsigned long round_hint_to_min(unsigned long hint)
{
#ifdef CONFIG_SECURITY
hint &= PAGE_MASK;
if (((void *)hint != NULL) &&
(hint < mmap_min_addr))
return PAGE_ALIGN(mmap_min_addr);
#endif
return hint;
}
/*
* Some inline functions in vmstat.h depend on page_zone()
*/
#include <linux/vmstat.h>
static __always_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;
VM_BUG_ON(PageSlab(page));
#ifdef CONFIG_SWAP
if (unlikely(PageSwapCache(page)))
mapping = &swapper_space;
else
#endif
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;
}
/*
* 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_MINOR 0 /* For backwards compat. Remove me quickly. */
#define VM_FAULT_OOM 0x0001
#define VM_FAULT_SIGBUS 0x0002
#define VM_FAULT_MAJOR 0x0004
#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
#define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */
#define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */
#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS)
#define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
extern void show_free_areas(void);
#ifdef CONFIG_SHMEM
extern int shmem_lock(struct file *file, int lock, struct user_struct *user);
#else
static inline int shmem_lock(struct file *file, int lock,
struct user_struct *user)
{
return 0;
}
#endif
struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags);
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
extern int can_do_mlock(void);
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 *vma, unsigned long addr,
pte_t pte);
int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
unsigned long size);
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 *);
/**
* mm_walk - callbacks for walk_page_range
* @pgd_entry: if set, called for each non-empty PGD (top-level) entry
* @pud_entry: if set, called for each non-empty PUD (2nd-level) entry
* @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
* @pte_entry: if set, called for each non-empty PTE (4th-level) entry
* @pte_hole: if set, called for each hole at all levels
*
* (see walk_page_range for more details)
*/
struct mm_walk {
int (*pgd_entry)(pgd_t *, unsigned long, unsigned long, struct mm_walk *);
int (*pud_entry)(pud_t *, unsigned long, unsigned long, struct mm_walk *);
int (*pmd_entry)(pmd_t *, unsigned long, unsigned long, struct mm_walk *);
int (*pte_entry)(pte_t *, unsigned long, unsigned long, struct mm_walk *);
int (*pte_hole)(unsigned long, unsigned long, struct mm_walk *);
struct mm_struct *mm;
void *private;
};
int walk_page_range(unsigned long addr, unsigned long end,
struct mm_walk *walk);
void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
unsigned long end, unsigned long floor, unsigned long ceiling);
int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
struct vm_area_struct *vma);
void unmap_mapping_range(struct address_space *mapping,
loff_t const holebegin, loff_t const holelen, int even_cows);
int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
void *buf, int len, int write);
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 vmtruncate_range(struct inode * inode, loff_t offset, loff_t end);
#ifdef CONFIG_MMU
extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, int write_access);
#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);
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);
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_nobuffers(struct page *page);
int __set_page_dirty_no_writeback(struct page *page);
int redirty_page_for_writepage(struct writeback_control *wbc,
struct page *page);
int 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 move_page_tables(struct vm_area_struct *vma,
unsigned long old_addr, struct vm_area_struct *new_vma,
unsigned long new_addr, unsigned long len);
extern unsigned long do_mremap(unsigned long addr,
unsigned long old_len, unsigned long new_len,
unsigned long flags, unsigned long new_addr);
extern int mprotect_fixup(struct vm_area_struct *vma,
struct vm_area_struct **pprev, unsigned long start,
unsigned long end, unsigned long newflags);
/*
* get_user_pages_fast provides equivalent functionality to get_user_pages,
* operating on current and current->mm (force=0 and doesn't return any vmas).
*
* get_user_pages_fast may take mmap_sem and page tables, so no assumptions
* can be made about locking. get_user_pages_fast is to be implemented in a
* way that is advantageous (vs get_user_pages()) when the user memory area is
* already faulted in and present in ptes. However if the pages have to be
* faulted in, it may turn out to be slightly slower).
*/
int get_user_pages_fast(unsigned long start, int nr_pages, int write,
struct page **pages);
/*
* A callback you can register to apply pressure to ageable caches.
*
* 'shrink' is passed a count 'nr_to_scan' and a 'gfpmask'. It should
* look through the least-recently-used 'nr_to_scan' entries and
* attempt to free them up. It should return the number of objects
* which remain in the cache. If it returns -1, it means it cannot do
* any scanning at this time (eg. there is a risk of deadlock).
*
* The 'gfpmask' refers to the allocation we are currently trying to
* fulfil.
*
* Note that 'shrink' will be passed nr_to_scan == 0 when the VM is
* querying the cache size, so a fastpath for that case is appropriate.
*/
struct shrinker {
int (*shrink)(int nr_to_scan, gfp_t gfp_mask);
int seeks; /* seeks to recreate an obj */
/* These are for internal use */
struct list_head list;
long nr; /* objs pending delete */
};
#define DEFAULT_SEEKS 2 /* A good number if you don't know better. */
extern void register_shrinker(struct shrinker *);
extern void unregister_shrinker(struct shrinker *);
int vma_wants_writenotify(struct vm_area_struct *vma);
extern pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr, spinlock_t **ptl);
#ifdef __PAGETABLE_PUD_FOLDED
static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd,
unsigned long address)
{
return 0;
}
#else
int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
#endif
#ifdef __PAGETABLE_PMD_FOLDED
static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
unsigned long address)
{
return 0;
}
#else
int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);
#endif
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 USE_SPLIT_PTLOCKS
/*
* 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 /* !USE_SPLIT_PTLOCKS */
/*
* 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 /* USE_SPLIT_PTLOCKS */
static inline void pgtable_page_ctor(struct page *page)
{
pte_lock_init(page);
inc_zone_page_state(page, NR_PAGETABLE);
}
static inline void pgtable_page_dtor(struct page *page)
{
pte_lock_deinit(page);
dec_zone_page_state(page, NR_PAGETABLE);
}
#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, unsigned long * zones_size,
unsigned long zone_start_pfn, unsigned long *zholes_size);
#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 remove_active_range(unsigned int nid, unsigned long start_pfn,
unsigned long 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 void free_bootmem_with_active_regions(int nid,
unsigned long max_low_pfn);
typedef int (*work_fn_t)(unsigned long, unsigned long, void *);
extern void work_with_active_regions(int nid, work_fn_t work_fn, void *data);
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);
extern int after_bootmem;
#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(struct mm_struct *mm, 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 mm_take_all_locks(struct mm_struct *mm);
extern void mm_drop_all_locks(struct mm_struct *mm);
#ifdef CONFIG_PROC_FS
/* From fs/proc/base.c. callers must _not_ hold the mm's exe_file_lock */
extern void added_exe_file_vma(struct mm_struct *mm);
extern void removed_exe_file_vma(struct mm_struct *mm);
#else
static inline void added_exe_file_vma(struct mm_struct *mm)
{}
static inline void removed_exe_file_vma(struct mm_struct *mm)
{}
#endif /* CONFIG_PROC_FS */
extern int may_expand_vm(struct mm_struct *mm, unsigned long npages);
extern int install_special_mapping(struct mm_struct *mm,
unsigned long addr, unsigned long len,
unsigned long flags, struct page **pages);
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);
extern unsigned long mmap_region(struct file *file, unsigned long addr,
unsigned long len, unsigned long flags,
unsigned int vm_flags, unsigned long pgoff,
int accountable);
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);
extern void truncate_inode_pages_range(struct address_space *,
loff_t lstart, loff_t lend);
/* generic vm_area_ops exported for stackable file systems */
extern int filemap_fault(struct vm_area_struct *, struct vm_fault *);
/* 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) */
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);
void page_cache_sync_readahead(struct address_space *mapping,
struct file_ra_state *ra,
struct file *filp,
pgoff_t offset,
unsigned long size);
void page_cache_async_readahead(struct address_space *mapping,
struct file_ra_state *ra,
struct file *filp,
struct page *pg,
pgoff_t offset,
unsigned long size);
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
extern int expand_stack_downwards(struct vm_area_struct *vma,
unsigned long address);
/* 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;
}
pgprot_t vm_get_page_prot(unsigned long vm_flags);
struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long 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 *);
int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
unsigned long pfn);
int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
unsigned long pfn);
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 */
typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, 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);
#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 */
#ifdef CONFIG_DEBUG_PAGEALLOC
extern int debug_pagealloc_enabled;
extern void kernel_map_pages(struct page *page, int numpages, int enable);
static inline void enable_debug_pagealloc(void)
{
debug_pagealloc_enabled = 1;
}
#ifdef CONFIG_HIBERNATION
extern bool kernel_page_present(struct page *page);
#endif /* CONFIG_HIBERNATION */
#else
static inline void
kernel_map_pages(struct page *page, int numpages, int enable) {}
static inline void enable_debug_pagealloc(void)
{
}
#ifdef CONFIG_HIBERNATION
static inline bool kernel_page_present(struct page *page) { return true; }
#endif /* CONFIG_HIBERNATION */
#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 */
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);
#ifndef CONFIG_MMU
#define randomize_va_space 0
#else
extern int randomize_va_space;
#endif
const char * arch_vma_name(struct vm_area_struct *vma);
void print_vma_addr(char *prefix, unsigned long rip);
struct page *sparse_mem_map_populate(unsigned long pnum, int nid);
pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
pud_t *vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node);
pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node);
void *vmemmap_alloc_block(unsigned long size, int node);
void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
int vmemmap_populate_basepages(struct page *start_page,
unsigned long pages, int node);
int vmemmap_populate(struct page *start_page, unsigned long pages, int node);
void vmemmap_populate_print_last(void);
#endif /* __KERNEL__ */
#endif /* _LINUX_MM_H */