網絡子係統1_socket文件係統相關的初始化
1.調用流程
start_kernel->rest_init->kernel_thread->init->do_basic_setup->do_initcalls->sock_init
//在do_basic_setup 中被調用
2.1 void __init sock_init(void)
{
//socket SLAB初始化
sk_init();
//skb SLAB初始化
skb_init();
//socket FS初始化
init_inodecache();
//socket文件係統類型
register_filesystem(&sock_fs_type);
sock_mnt = kern_mount(&sock_fs_type);
}
//將此函數入口添加到extern initcall_t __initcall_start[], __initcall_end[]之間
core_initcall(sock_init);
2.2 void __init sk_init(void)
{
//創建sock的SLAB cache
sk_cachep = kmem_cache_create("sock", sizeof(struct sock), 0,
SLAB_HWCACHE_ALIGN, NULL, NULL);
//下邊初始化一些閥值
....
}
//socket 的file_system_type
3.1 static struct file_system_type sock_fs_type = {
.name = "sockfs",
.get_sb = sockfs_get_sb,
.kill_sb = kill_anon_super,
};
//填充超級塊的方法
3.2 static struct super_block *sockfs_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
//偽文件係統獲取sb的helper函數
return get_sb_pseudo(fs_type, "socket:", &sockfs_ops, SOCKFS_MAGIC);
}
3.3 struct super_block *
get_sb_pseudo(struct file_system_type *fs_type, char *name,
struct super_operations *ops, unsigned long magic)
{
...
//設置超級塊的函數指針
s->s_op = ops ? ops : &default_ops;
...
}
3.4 static struct super_operations sockfs_ops = {
//分配,刪除inode的方法,通過在2.1中的inode cache分配
.alloc_inode = sock_alloc_inode,
.destroy_inode = sock_destroy_inode,
...
};
//至此,與socket有關的文件係統部分初始化完成
最後更新:2017-04-03 15:21:55