include/linux/mm.h

/* */
This source file includes following definitions.
get_free_page
   1 #ifndef _LINUX_MM_H
   2 #define _LINUX_MM_H
   3 
   4 #define PAGE_SIZE 4096
   5 #define PAGE_SHIFT 12
   6 
   7 #include <linux/fs.h>
   8 #include <linux/kernel.h>
   9 
  10 /*
  11  * Linux kernel virtual memory manager primitives.
  12  * The idea being to have a "virtual" mm in the same way
  13  * we have a virtual fs - giving a cleaner interface to the
  14  * mm details, and allowing different kinds of memory mappings
  15  * (from shared memory to executable loading to arbitrary
  16  * mmap() functions).
  17  */
  18 
  19 /*
  20  * This struct defines a memory VMM memory area. There is one of these
  21  * per VM-area/task.  A VM area is any part of the process virtual memory
  22  * space that has a special rule for the page-fault handlers (ie a shared
  23  * library, the executable area etc).
  24  */
  25 struct vm_area_struct {
  26         struct task_struct * vm_task;           /* VM area parameters */
  27         unsigned long vm_start;
  28         unsigned long vm_end;
  29         struct vm_area_struct * vm_next;        /* linked list */
  30         struct vm_area_struct * vm_share;       /* linked list */
  31         struct inode * vm_inode;
  32         unsigned long vm_offset;
  33         struct vm_operations_struct * vm_ops;
  34 };
  35 
  36 /*
  37  * These are the virtual MM functions - opening of an area, closing it (needed to
  38  * keep files on disk up-to-date etc), pointer to the functions called when a
  39  * no-page or a wp-page exception occurs, and the function which decides on sharing
  40  * of pages between different processes.
  41  */
  42 struct vm_operations_struct {
  43         void (*open)(struct vm_area_struct * area);
  44         void (*close)(struct vm_area_struct * area);
  45         void (*nopage)(struct vm_area_struct * area, unsigned long address);
  46         void (*wppage)(struct vm_area_struct * area, unsigned long address);
  47         int (*share)(struct vm_area_struct * old, struct vm_area_struct * new, unsigned long address);
  48 };
  49 
  50 extern unsigned long __bad_page(void);
  51 extern unsigned long __bad_pagetable(void);
  52 extern unsigned long __zero_page(void);
  53 
  54 #define BAD_PAGETABLE __bad_pagetable()
  55 #define BAD_PAGE __bad_page()
  56 #define ZERO_PAGE __zero_page()
  57 
  58 extern volatile short free_page_ptr; /* used by malloc and tcp/ip. */
  59 
  60 extern int nr_free_pages;
  61 extern unsigned long free_page_list;
  62 extern int nr_secondary_pages;
  63 extern unsigned long secondary_page_list;
  64 
  65 #define MAX_SECONDARY_PAGES 10
  66 
  67 /*
  68  * This is timing-critical - most of the time in getting a new page
  69  * goes to clearing the page. If you want a page without the clearing
  70  * overhead, just use __get_free_page() directly..
  71  */
  72 extern unsigned long __get_free_page(int priority);
  73 extern inline unsigned long get_free_page(int priority)
     /*  */
  74 {
  75         unsigned long page;
  76 
  77         page = __get_free_page(priority);
  78         if (page)
  79                 __asm__ __volatile__("rep ; stosl"
  80                         ::"a" (0),"c" (1024),"D" (page)
  81                         :"di","cx");
  82         return page;
  83 }
  84 
  85 /* mmap.c */
  86 
  87 /* memory.c */
  88 
  89 extern void free_page(unsigned long addr);
  90 extern unsigned long put_dirty_page(struct task_struct * tsk,unsigned long page,
  91         unsigned long address);
  92 extern void free_page_tables(struct task_struct * tsk);
  93 extern void clear_page_tables(struct task_struct * tsk);
  94 extern int copy_page_tables(struct task_struct * new);
  95 extern int clone_page_tables(struct task_struct * new);
  96 extern int unmap_page_range(unsigned long from, unsigned long size);
  97 extern int remap_page_range(unsigned long from, unsigned long to, unsigned long size, int mask);
  98 extern int zeromap_page_range(unsigned long from, unsigned long size, int mask);
  99 
 100 extern void do_wp_page(unsigned long error_code, unsigned long address,
 101         struct task_struct *tsk, unsigned long user_esp);
 102 extern void do_no_page(unsigned long error_code, unsigned long address,
 103         struct task_struct *tsk, unsigned long user_esp);
 104 
 105 extern unsigned long paging_init(unsigned long start_mem, unsigned long end_mem);
 106 extern void mem_init(unsigned long low_start_mem,
 107                      unsigned long start_mem, unsigned long end_mem);
 108 extern void show_mem(void);
 109 extern void do_page_fault(unsigned long *esp, unsigned long error_code);
 110 extern void oom(struct task_struct * task);
 111 extern void si_meminfo(struct sysinfo * val);
 112 
 113 /* swap.c */
 114 
 115 extern void swap_free(unsigned long page_nr);
 116 extern unsigned long swap_duplicate(unsigned long page_nr);
 117 extern void swap_in(unsigned long *table_ptr);
 118 extern void si_swapinfo(struct sysinfo * val);
 119 extern void rw_swap_page(int rw, unsigned long nr, char * buf);
 120 
 121 #define read_swap_page(nr,buf) \
 122         rw_swap_page(READ,(nr),(buf))
 123 #define write_swap_page(nr,buf) \
 124         rw_swap_page(WRITE,(nr),(buf))
 125 
 126 #define invalidate() \
 127 __asm__ __volatile__("movl %%cr3,%%eax\n\tmovl %%eax,%%cr3":::"ax")
 128 
 129 extern unsigned long high_memory;
 130 
 131 #define MAP_NR(addr) ((addr) >> PAGE_SHIFT)
 132 #define MAP_PAGE_RESERVED (1<<15)
 133 
 134 extern unsigned short * mem_map;
 135 
 136 #define PAGE_PRESENT    0x001
 137 #define PAGE_RW         0x002
 138 #define PAGE_USER       0x004
 139 #define PAGE_PWT        0x008   /* 486 only - not used currently */
 140 #define PAGE_PCD        0x010   /* 486 only - not used currently */
 141 #define PAGE_ACCESSED   0x020
 142 #define PAGE_DIRTY      0x040
 143 #define PAGE_COW        0x200   /* implemented in software (one of the AVL bits) */
 144 
 145 #define PAGE_PRIVATE    (PAGE_PRESENT | PAGE_RW | PAGE_USER | PAGE_ACCESSED | PAGE_COW)
 146 #define PAGE_SHARED     (PAGE_PRESENT | PAGE_RW | PAGE_USER | PAGE_ACCESSED)
 147 #define PAGE_COPY       (PAGE_PRESENT | PAGE_USER | PAGE_ACCESSED | PAGE_COW)
 148 #define PAGE_READONLY   (PAGE_PRESENT | PAGE_USER | PAGE_ACCESSED)
 149 #define PAGE_TABLE      (PAGE_PRESENT | PAGE_RW | PAGE_USER | PAGE_ACCESSED)
 150 
 151 #define GFP_BUFFER      0x00
 152 #define GFP_ATOMIC      0x01
 153 #define GFP_USER        0x02
 154 #define GFP_KERNEL      0x03
 155 
 156 #endif
/* */
root/include/linux/mm.h

INCLUDED FROM

DEFINITIONS
