Linux内核虚拟内存的管理结构说明

  1 一块虚拟内存空间用该结构来表示，然后所有的虚拟地址空间块构成了一个链表。并且形成了一个AVL树。便于查找。
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  4 Vm_area_struct 结构。
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  6 Typedef struct  tag_vm_area_struct
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  8 {
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 10 Struct mm_struct* mm;
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 12 
 13 //决定了一个虚拟地址空间的Start和End
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 15      Unsigned long    vm_start;
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 17  Unsigned long    vm_end;
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 20 //该块空间的访问属性和其他属性
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 22  Pgprot_t vm_page_prot;
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 24  Unsigned long  vm_flags;
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 26 
 27 //虚拟地址空间块的链表
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 29 Struct vm_area_struct *  vm_next;
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 32 //虚拟地址空间块的AVL树
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 34 Short vm_avl_height;
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 36 Struct vm_area_struct *  vm_avl_left;
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 38 Struct vm_area_struct *  vm_avl_right;
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 41 Struct vm_operational_struct * vm_ops;
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 43 
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 45 Struct vm_area_struct *  vm_next_share;
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 47 Struct vm_area_struct *  vm_pprev_share;
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 49 
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 51 Unsigned long      vm_pgoff;
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 54 Struct file *   vm_file;
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 56 
 57 Unsigned long    vm_raend;
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 60 Void * vm_private_data;
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 62 
 63 }vm_area_struct;
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 68 Mm_struct 结构
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 70 
 71 是进程整个用户空间的抽象。
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 74 Struct mm_struct 
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 76 {
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 78 Struct vm_area_struct *   mmap;   //vm区域的链表头
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 80 Struct vm_area_struct *   mmap_avl;   //vm的avl树
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 82 Struct vm_area_struct *   mmap_cache;   //vm区域缓冲cache
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 85 Pgd_t  * pgd;       //页面目录表
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 88 Atomic_t    mm_users; 
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 90 Atomic_t    mm_count;
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 92 
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 94 //vm的个数
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 96 Int          mapcount;
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 99 Struct semaphore mmap_sem;
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102 Spinlock_t    page_table_lock;
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105 Stuct list_head    mmlist;
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107 
108 Unsigned long  start_code, end_code, start_data, end_data;
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111 Unsigned long  start_brk, brk, start_stack;
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114 Unsigned long   arg_start, arg_end, env_start, env_end;
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117 Unsigned long   rss, total_vm, locked_vm;
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119 Unsigned long   def_flags;
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121 Unsigned long   cpu_vm_mask;
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123 Unsigned long   swap_cnt;
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125 Unsigned long   swap_address;
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127 Mm_context_t   context;
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129 };
130