Linux进程地址空间之初探：一

1 structmm_struct {
2     struct vm_area_struct * mmap;        /*list of VMAs */
3     structrb_root mm_rb;
4     struct vm_area_struct * mmap_cache;    /*last find_vma result */
5     unsigned long free_area_cache;        /*first hole */
6     pgd_t *pgd;
7     atomic_t mm_users;            /*How many users with user space? */
8     atomic_t mm_count;            /*How many references to "struct mm_struct" (users count as 1) */
9     int map_count;                /*number of VMAs */
10     structrw_semaphore mmap_sem;
11     spinlock_t page_table_lock;        /*Protects task page tables and mm->rss */
12 
13     struct list_head mmlist;        /*List of all active mm's.  These are globally strung
14 * together off init_mm.mmlist, and are protected
15 * by mmlist_lock
16                          */
17 
18     unsigned longstart_code, end_code, start_data, end_data;
19     unsigned longstart_brk, brk, start_stack;
20     unsigned longarg_start, arg_end, env_start, env_end;
21     unsigned longrss, total_vm, locked_vm;
22     unsigned longdef_flags;
23 
24     unsigned long saved_auxv[40]; /*for /proc/PID/auxv */
25 
26     unsigned dumpable:1;
27 cpumask_t cpu_vm_mask;
28 
29     /*Architecture-specific MM context */
30 mm_context_t context;
31 
32     /*coredumping support */
33     intcore_waiters;
34     struct completion *core_startup_done, core_done;
35 
36     /*aio bits */
37 rwlock_t        ioctx_list_lock;
38     struct kioctx        *ioctx_list;
39 
40     structkioctx        default_kioctx;
41 };

1 structvm_area_struct {
2     struct mm_struct * vm_mm;    /*The address space we belong to. */
3     unsigned long vm_start;        /*Our start address within vm_mm. */
4     unsigned long vm_end;        /*The first byte after our end address
5 within vm_mm. */
6 
7     /*linked list of VM areas per task, sorted by address */
8     struct vm_area_struct *vm_next;
9 
10     pgprot_t vm_page_prot;        /*Access permissions of this VMA. */
11     unsigned long vm_flags;        /*Flags, listed below. */
12 
13     structrb_node vm_rb;
14 
15     /*
16 * For areas with an address space and backing store,
17 * linkage into the address_space->i_mmap prio tree, or
18 * linkage to the list of like vmas hanging off its node, or
19 * linkage of vma in the address_space->i_mmap_nonlinear list.
20      */
21 union {
22         struct{
23             structlist_head list;
24             void *parent;    /*aligns with prio_tree_node parent */
25             struct vm_area_struct *head;
26 } vm_set;
27 
28         structprio_tree_node prio_tree_node;
29 } shared;
30 
31     /*
32 * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma
33 * list, after a COW of one of the file pages.  A MAP_SHARED vma
34 * can only be in the i_mmap tree.  An anonymous MAP_PRIVATE, stack
35 * or brk vma (with NULL file) can only be in an anon_vma list.
36      */
37     struct list_head anon_vma_node;    /*Serialized by anon_vma->lock */
38     struct anon_vma *anon_vma;    /*Serialized by page_table_lock */
39 
40     /*Function pointers to deal with this struct. */
41     struct vm_operations_struct *vm_ops;
42 
43     /*Information about our backing store: */
44     unsigned long vm_pgoff;        /*Offset (within vm_file) in PAGE_SIZE
45 units, *not* PAGE_CACHE_SIZE */
46     struct file * vm_file;        /*File we map to (can be NULL). */
47     void * vm_private_data;        /*was vm_pte (shared mem) */
48 
49 #ifdef CONFIG_NUMA
50     struct mempolicy *vm_policy;    /*NUMA policy for the VMA */
51 #endif
52 };

hello.c
1 #include<stdio.h>
2 intmain()
3 {
4     
5     printf("Hello\n");
6     return 0;
7 }