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#ifndef _LINUX_MM_H

#define _LINUX_MM_H

#include <linux/sched.h>

#include <linux/errno.h>

#ifdef __KERNEL__

#include <linux/config.h>

#include <linux/string.h>

#include <linux/list.h>

#include <linux/mmzone.h>

#include <linux/swap.h>

#include <linux/rbtree.h>

extern unsigned long max_mapnr;

extern unsigned long num_physpages;

extern unsigned long num_mappedpages;

extern void * high_memory;

extern int page_cluster;

/* The inactive_clean lists are per zone. */

extern struct list_head active_list;

extern struct list_head inactive_list;

#include <asm/page.h>

#include <asm/pgtable.h>

#include <asm/atomic.h>

/*

 * 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. */

        rb_node_t vm_rb;

        /*

         * For areas with an address space and backing store,

         * one of the address_space->i_mmap{,shared} lists,

         * for shm areas, the list of attaches, otherwise unused.

         */

        struct vm_area_struct *vm_next_share;

        struct vm_area_struct **vm_pprev_share;

        /* 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). */

        unsigned long vm_raend;         /* XXX: put full readahead info here. */

        void * vm_private_data;         /* was vm_pte (shared mem) */

};

/*

 * vm_flags..

 */

#define VM_READ         0x00000001      /* currently active flags */

#define VM_WRITE        0x00000002

#define VM_EXEC         0x00000004

#define VM_SHARED       0x00000008

#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          0x00000400      /* shared memory area, don't swap out */

#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      /* Don't unmap it from swap_out */

#ifndef VM_STACK_FLAGS

#define VM_STACK_FLAGS  0x00000177

#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)

/* read ahead limits */

extern int vm_min_readahead;

extern int vm_max_readahead;

/*

 * 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 unused);

};

/*

 * 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.

 *

 * Try to keep the most commonly accessed fields in single cache lines

 * here (16 bytes or greater).  This ordering should be particularly

 * beneficial on 32-bit processors.

 *

 * The first line is data used in page cache lookup, the second line

 * is used for linear searches (eg. clock algorithm scans).

 *

 * TODO: make this structure smaller, it could be as small as 32 bytes.

 */

typedef struct page {

        struct list_head list;          /* ->mapping has some page lists. */

        struct address_space *mapping;  /* The inode (or ...) we belong to. */

        unsigned long index;            /* Our offset within mapping. */

        struct page *next_hash;         /* Next page sharing our hash bucket in

                                           the pagecache hash table. */

        atomic_t count;                 /* Usage count, see below. */

        unsigned long flags;            /* atomic flags, some possibly

                                           updated asynchronously */

        struct list_head lru;           /* Pageout list, eg. active_list;

                                           protected by pagemap_lru_lock !! */

        struct page **pprev_hash;       /* Complement to *next_hash. */

        struct buffer_head * buffers;   /* Buffer maps us to a disk block. */

        /*

         * 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(CONFIG_HIGHMEM) || defined(WANT_PAGE_VIRTUAL)

        void *virtual;                  /* Kernel virtual address (NULL if

                                           not kmapped, ie. highmem) */

#endif /* CONFIG_HIGMEM || WANT_PAGE_VIRTUAL */

} mem_map_t;

/*

 * Methods to modify the page usage count.

 *

 * What counts for a page usage:

 * - cache mapping   (page->mapping)

 * - disk mapping    (page->buffers)

 * - 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.

 */

#define get_page(p)             atomic_inc(&(p)->count)

#define put_page(p)             __free_page(p)

#define put_page_testzero(p)    atomic_dec_and_test(&(p)->count)

#define page_count(p)           atomic_read(&(p)->count)

#define set_page_count(p,v)     atomic_set(&(p)->count, v)

/*

 * Various page->flags bits:

 *

 * PG_reserved is set for special pages, which can never be swapped

 * out. Some of them might not even exist (eg empty_bad_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 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).

 *

 * 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 may have buffers allocated to it. In this case,

 * page->buffers is a circular list of these buffer heads. Else,

 * page->buffers == NULL.

 *

 * For pages belonging to inodes, the page->count is the number of

 * attaches, plus 1 if buffers are allocated to the page, plus one

 * for the page cache itself.

 *

 * 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).

 *

 * There is also a hash table mapping (mapping,index) to the page

 * in memory if present. The lists for this hash table use the fields

 * page->next_hash and page->pprev_hash.

 *

 * 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.

 * During disk I/O, PG_locked is used. This bit is set before I/O

 * and reset when I/O completes. page_waitqueue(page) is a wait queue of all

 * tasks waiting for the I/O on this page to complete.

 * PG_uptodate tells whether the page's contents is valid.

 * When a read completes, the page becomes uptodate, unless a disk I/O

 * error happened.

 *

 * For choosing which pages to swap out, inode pages carry a

 * PG_referenced bit, which is set any time the system accesses

 * that page through the (mapping,index) hash table. This referenced

 * bit, together with the referenced bit in the page tables, is used

 * to manipulate page->age and move the page across the active,

 * inactive_dirty and inactive_clean lists.

 *

 * Note that the referenced bit, the page->lru list_head and the

 * active, inactive_dirty and inactive_clean lists are protected by

 * the pagemap_lru_lock, and *NOT* by the usual PG_locked bit!

 *

 * PG_skip is used on sparc/sparc64 architectures to "skip" certain

 * parts of the address space.

 *

 * PG_error is set to indicate that an I/O error occurred on this page.

 *

 * PG_arch_1 is an architecture specific page state bit.  The generic

 * code guarantees that this bit is cleared for a page when it first

 * is entered into the page cache.

 *

 * PG_highmem pages are not permanently mapped into the kernel virtual

 * address space, they need to be kmapped separately for doing IO on

 * the pages. The struct page (these bits with information) are always

 * mapped into kernel address space...

 */

#define PG_locked                0      /* Page is locked. Don't touch. */

#define PG_error                 1

#define PG_referenced            2

#define PG_uptodate              3

#define PG_dirty                 4

#define PG_unused                5

#define PG_lru                   6

#define PG_active                7

#define PG_slab                  8

#define PG_skip                 10

#define PG_highmem              11

#define PG_checked              12      /* kill me in 2.5.<early>. */

#define PG_arch_1               13

#define PG_reserved             14

#define PG_launder              15      /* written out by VM pressure.. */

#define PG_fs_1                 16      /* Filesystem specific */

#ifndef arch_set_page_uptodate

#define arch_set_page_uptodate(page)

#endif

/* Make it prettier to test the above... */

#define UnlockPage(page)        unlock_page(page)

#define Page_Uptodate(page)     test_bit(PG_uptodate, &(page)->flags)

#define SetPageUptodate(page) \

        do {                                                            \

                arch_set_page_uptodate(page);                           \

                set_bit(PG_uptodate, &(page)->flags);                   \

        } while (0)

#define ClearPageUptodate(page) clear_bit(PG_uptodate, &(page)->flags)

#define PageDirty(page)         test_bit(PG_dirty, &(page)->flags)

#define SetPageDirty(page)      set_bit(PG_dirty, &(page)->flags)

#define ClearPageDirty(page)    clear_bit(PG_dirty, &(page)->flags)

#define PageLocked(page)        test_bit(PG_locked, &(page)->flags)

#define LockPage(page)          set_bit(PG_locked, &(page)->flags)

#define TryLockPage(page)       test_and_set_bit(PG_locked, &(page)->flags)

#define PageChecked(page)       test_bit(PG_checked, &(page)->flags)

#define SetPageChecked(page)    set_bit(PG_checked, &(page)->flags)

#define ClearPageChecked(page)  clear_bit(PG_checked, &(page)->flags)

#define PageLaunder(page)       test_bit(PG_launder, &(page)->flags)

#define SetPageLaunder(page)    set_bit(PG_launder, &(page)->flags)

#define ClearPageLaunder(page)  clear_bit(PG_launder, &(page)->flags)

#define ClearPageArch1(page)    clear_bit(PG_arch_1, &(page)->flags)

/*

 * The zone field is never updated after free_area_init_core()

 * sets it, so none of the operations on it need to be atomic.

 */

#define NODE_SHIFT 4

#define ZONE_SHIFT (BITS_PER_LONG - 8)

struct zone_struct;

extern struct zone_struct *zone_table[];

static inline zone_t *page_zone(struct page *page)

{

        return zone_table[page->flags >> ZONE_SHIFT];

}

static inline void set_page_zone(struct page *page, unsigned long zone_num)

{

        page->flags &= ~(~0UL << ZONE_SHIFT);

        page->flags |= zone_num << ZONE_SHIFT;

}

/*

 * In order to avoid #ifdefs within C code itself, we define

 * set_page_address to a noop for non-highmem machines, where

 * the field isn't useful.

 * The same is true for page_address() in arch-dependent code.

 */

#if defined(CONFIG_HIGHMEM) || defined(WANT_PAGE_VIRTUAL)

#define set_page_address(page, address)                 \

        do {                                            \

                (page)->virtual = (address);            \

        } while(0)

#else /* CONFIG_HIGHMEM || WANT_PAGE_VIRTUAL */

#define set_page_address(page, address)  do { } while(0)

#endif /* CONFIG_HIGHMEM || WANT_PAGE_VIRTUAL */

/*

 * Permanent address of a page. Obviously must never be

 * called on a highmem page.

 */

#if defined(CONFIG_HIGHMEM) || defined(WANT_PAGE_VIRTUAL)

#define page_address(page) ((page)->virtual)

#else /* CONFIG_HIGHMEM || WANT_PAGE_VIRTUAL */

#define page_address(page)                                              \

        __va( (((page) - page_zone(page)->zone_mem_map) << PAGE_SHIFT)  \

                        + page_zone(page)->zone_start_paddr)

#endif /* CONFIG_HIGHMEM || WANT_PAGE_VIRTUAL */

extern void FASTCALL(set_page_dirty(struct page *));

/*

 * The first mb is necessary to safely close the critical section opened by the

 * TryLockPage(), the second mb is necessary to enforce ordering between

 * the clear_bit and the read of the waitqueue (to avoid SMP races with a

 * parallel wait_on_page).

 */

#define PageError(page)         test_bit(PG_error, &(page)->flags)

#define SetPageError(page)      set_bit(PG_error, &(page)->flags)

#define ClearPageError(page)    clear_bit(PG_error, &(page)->flags)

#define PageReferenced(page)    test_bit(PG_referenced, &(page)->flags)

#define SetPageReferenced(page) set_bit(PG_referenced, &(page)->flags)

#define ClearPageReferenced(page)       clear_bit(PG_referenced, &(page)->flags)

#define PageTestandClearReferenced(page)        test_and_clear_bit(PG_referenced, &(page)->flags)

#define PageSlab(page)          test_bit(PG_slab, &(page)->flags)

#define PageSetSlab(page)       set_bit(PG_slab, &(page)->flags)

#define PageClearSlab(page)     clear_bit(PG_slab, &(page)->flags)

#define PageReserved(page)      test_bit(PG_reserved, &(page)->flags)

#define PageActive(page)        test_bit(PG_active, &(page)->flags)

#define SetPageActive(page)     set_bit(PG_active, &(page)->flags)

#define ClearPageActive(page)   clear_bit(PG_active, &(page)->flags)

#define PageLRU(page)           test_bit(PG_lru, &(page)->flags)

#define TestSetPageLRU(page)    test_and_set_bit(PG_lru, &(page)->flags)

#define TestClearPageLRU(page)  test_and_clear_bit(PG_lru, &(page)->flags)

#ifdef CONFIG_HIGHMEM

#define PageHighMem(page)               test_bit(PG_highmem, &(page)->flags)

#else

#define PageHighMem(page)               0 /* needed to optimize away at compile time */

#endif

#define SetPageReserved(page)           set_bit(PG_reserved, &(page)->flags)

#define ClearPageReserved(page)         clear_bit(PG_reserved, &(page)->flags)

/*

 * Error return values for the *_nopage functions

 */

#define NOPAGE_SIGBUS   (NULL)

#define NOPAGE_OOM      ((struct page *) (-1))

/* The array of struct pages */

extern mem_map_t * mem_map;

/*

 * There is only one page-allocator function, and two main namespaces to

 * it. The alloc_page*() variants return 'struct page *' and as such

 * can allocate highmem pages, the *get*page*() variants return

 * virtual kernel addresses to the allocated page(s).

 */

extern struct page * FASTCALL(_alloc_pages(unsigned int gfp_mask, unsigned int order));

extern struct page * FASTCALL(__alloc_pages(unsigned int gfp_mask, unsigned int order, zonelist_t *zonelist));

extern struct page * alloc_pages_node(int nid, unsigned int gfp_mask, unsigned int order);

static inline struct page * alloc_pages(unsigned int gfp_mask, unsigned int order)

{

        /*

         * Gets optimized away by the compiler.

         */

        if (order >= MAX_ORDER)

                return NULL;

        return _alloc_pages(gfp_mask, order);

}

#define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)

extern unsigned long FASTCALL(__get_free_pages(unsigned int gfp_mask, unsigned int order));

extern unsigned long FASTCALL(get_zeroed_page(unsigned int gfp_mask));

#define __get_free_page(gfp_mask) \

                __get_free_pages((gfp_mask),0)

#define __get_dma_pages(gfp_mask, order) \

                __get_free_pages((gfp_mask) | GFP_DMA,(order))

/*

 * The old interface name will be removed in 2.5:

 */

#define get_free_page get_zeroed_page

/*

 * There is only one 'core' page-freeing function.

 */

extern void FASTCALL(__free_pages(struct page *page, unsigned int order));

extern void FASTCALL(free_pages(unsigned long addr, unsigned int order));

#define __free_page(page) __free_pages((page), 0)

#define free_page(addr) free_pages((addr),0)

extern void show_free_areas(void);

extern void show_free_areas_node(pg_data_t *pgdat);

extern void clear_page_tables(struct mm_struct *, unsigned long, int);

extern int fail_writepage(struct page *);

struct page * shmem_nopage(struct vm_area_struct * vma, unsigned long address, int unused);

struct file *shmem_file_setup(char * name, loff_t size);

extern void shmem_lock(struct file * file, int lock);

extern int shmem_zero_setup(struct vm_area_struct *);

extern void zap_page_range(struct mm_struct *mm, unsigned long address, unsigned long size);

extern int copy_page_range(struct mm_struct *dst, struct mm_struct *src, struct vm_area_struct *vma);

extern int remap_page_range(unsigned long from, unsigned long to, unsigned long size, pgprot_t prot);

extern int zeromap_page_range(unsigned long from, unsigned long size, pgprot_t prot);

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(struct mm_struct *mm, pmd_t *pmd, unsigned long address));

extern int handle_mm_fault(struct mm_struct *mm,struct vm_area_struct *vma, unsigned long address, int write_access);

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);

extern int ptrace_readdata(struct task_struct *tsk, unsigned long src, char *dst, int len);

extern int ptrace_writedata(struct task_struct *tsk, char * src, unsigned long dst, int len);

extern int ptrace_attach(struct task_struct *tsk);

extern int ptrace_detach(struct task_struct *, unsigned int);

extern void ptrace_disable(struct task_struct *);

extern int ptrace_check_attach(struct task_struct *task, int kill);

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);

/*

 * On a two-level page table, this ends up being trivial. Thus the

 * inlining and the symmetry break with pte_alloc() that does all

 * of this out-of-line.

 */

static inline pmd_t *pmd_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)

{

        if (pgd_none(*pgd))

                return __pmd_alloc(mm, pgd, address);

        return pmd_offset(pgd, address);

}

extern int pgt_cache_water[2];

extern int check_pgt_cache(void);

extern void free_area_init(unsigned long * zones_size);

extern void free_area_init_node(int nid, pg_data_t *pgdat, struct page *pmap,

        unsigned long * zones_size, unsigned long zone_start_paddr,

        unsigned long *zholes_size);

extern void mem_init(void);

extern void show_mem(void);

extern void si_meminfo(struct sysinfo * val);

extern void swapin_readahead(swp_entry_t);

extern struct address_space swapper_space;

#define PageSwapCache(page) ((page)->mapping == &swapper_space)

static inline int is_page_cache_freeable(struct page * page)

{

        return page_count(page) - !!page->buffers == 1;

}

extern int FASTCALL(can_share_swap_page(struct page *));

extern int FASTCALL(remove_exclusive_swap_page(struct page *));

extern void __free_pte(pte_t);

/* mmap.c */

extern void lock_vma_mappings(struct vm_area_struct *);

extern void unlock_vma_mappings(struct vm_area_struct *);

extern void insert_vm_struct(struct mm_struct *, struct vm_area_struct *);

extern void __insert_vm_struct(struct mm_struct *, struct vm_area_struct *);

extern void build_mmap_rb(struct mm_struct *);

extern void exit_mmap(struct mm_struct *);

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);

static inline void __vma_unlink(struct mm_struct * mm, struct vm_area_struct * vma, struct vm_area_struct * prev)

{

        prev->vm_next = vma->vm_next;

        rb_erase(&vma->vm_rb, &mm->mm_rb);

        if (mm->mmap_cache == vma)

                mm->mmap_cache = prev;

}

static inline int can_vma_merge(struct vm_area_struct * vma, unsigned long vm_flags)

{

        if (!vma->vm_file && vma->vm_flags == vm_flags)

                return 1;

        else

                return 0;

}

struct zone_t;

/* filemap.c */

extern void remove_inode_page(struct page *);

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 int filemap_sync(struct vm_area_struct *, unsigned long, size_t, unsigned int);

extern struct page *filemap_nopage(struct vm_area_struct *, unsigned long, int);

/*

 * GFP bitmasks..

 */

/* Zone modifiers in GFP_ZONEMASK (see linux/mmzone.h - low four bits) */

#define __GFP_DMA       0x01

#define __GFP_HIGHMEM   0x02

/* Action modifiers - doesn't change the zoning */

#define __GFP_WAIT      0x10    /* Can wait and reschedule? */

#define __GFP_HIGH      0x20    /* Should access emergency pools? */

#define __GFP_IO        0x40    /* Can start low memory physical IO? */

#define __GFP_HIGHIO    0x80    /* Can start high mem physical IO? */

#define __GFP_FS        0x100   /* Can call down to low-level FS? */

#define GFP_NOHIGHIO    (__GFP_HIGH | __GFP_WAIT | __GFP_IO)

#define GFP_NOIO        (__GFP_HIGH | __GFP_WAIT)

#define GFP_NOFS        (__GFP_HIGH | __GFP_WAIT | __GFP_IO | __GFP_HIGHIO)

#define GFP_ATOMIC      (__GFP_HIGH)

#define GFP_USER        (             __GFP_WAIT | __GFP_IO | __GFP_HIGHIO | __GFP_FS)

#define GFP_HIGHUSER    (             __GFP_WAIT | __GFP_IO | __GFP_HIGHIO | __GFP_FS | __GFP_HIGHMEM)

#define GFP_KERNEL      (__GFP_HIGH | __GFP_WAIT | __GFP_IO | __GFP_HIGHIO | __GFP_FS)

#define GFP_NFS         (__GFP_HIGH | __GFP_WAIT | __GFP_IO | __GFP_HIGHIO | __GFP_FS)

#define GFP_KSWAPD      (             __GFP_WAIT | __GFP_IO | __GFP_HIGHIO | __GFP_FS)

/* Flag - indicates that the buffer will be suitable for DMA.  Ignored on some

   platforms, used as appropriate on others */

#define GFP_DMA         __GFP_DMA

static inline unsigned int pf_gfp_mask(unsigned int gfp_mask)

{

        /* avoid all memory balancing I/O methods if this task cannot block on I/O */

        if (current->flags & PF_NOIO)

                gfp_mask &= ~(__GFP_IO | __GFP_HIGHIO | __GFP_FS);

        return gfp_mask;

}

/* vma is the first one with  address < vma->vm_end,

 * and even  address < vma->vm_start. Have to extend vma. */

static inline int expand_stack(struct vm_area_struct * vma, unsigned long address)

{

        unsigned long grow;

        /*

         * vma->vm_start/vm_end cannot change under us because the caller is required

         * to hold the mmap_sem in write mode. We need to get the spinlock only

         * before relocating the vma range ourself.

         */

        address &= PAGE_MASK;

        spin_lock(&vma->vm_mm->page_table_lock);

        grow = (vma->vm_start - address) >> PAGE_SHIFT;

        if (vma->vm_end - address > current->rlim[RLIMIT_STACK].rlim_cur ||

            ((vma->vm_mm->total_vm + grow) << PAGE_SHIFT) > current->rlim[RLIMIT_AS].rlim_cur) {

                spin_unlock(&vma->vm_mm->page_table_lock);

                return -ENOMEM;

        }

        vma->vm_start = address;

        vma->vm_pgoff -= grow;

        vma->vm_mm->total_vm += grow;

        if (vma->vm_flags & VM_LOCKED)

                vma->vm_mm->locked_vm += grow;

        spin_unlock(&vma->vm_mm->page_table_lock);

        return 0;

}

/* 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;

}

extern struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr);

extern struct page * vmalloc_to_page(void *addr);

#endif /* __KERNEL__ */

#endif