网络子系统1_socket文件系统相关的初始化

1.调用流程start_kernel->rest_init->kernel_thread->init->do_basic_setup->do_initcalls->sock_init//在do_basic_setup 中被调用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文件系统类型register_filesystem(&sock_fs_type);sock_mnt = kern_mount(&sock_fs_type);}//将此函数入口添加到extern initcall_t __initcall_start[], __initcall_end[]之间core_initcall(sock_init);2.2 void __init sk_init(void){//创建sock的SLAB cachesk_cachep = kmem_cache_create("sock", sizeof(struct sock), 0,      SLAB_HWCACHE_ALIGN, NULL, NULL);//下边初始化一些阀值....}//socket 的file_system_type3.1 static struct file_system_type sock_fs_type = {.name ="sockfs",.get_sb =sockfs_get_sb,.kill_sb =kill_anon_super,};//填充超级块的方法3.2 static struct super_block *sockfs_get_sb(struct file_system_type *fs_type,int flags, const char *dev_name, void *data){//伪文件系统获取sb的helper函数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){...//设置超级块的函数指针s->s_op = ops ? ops : &default_ops;...}3.4 static struct super_operations sockfs_ops = {//分配，删除inode的方法，通过在2.1中的inode cache分配.alloc_inode =sock_alloc_inode,.destroy_inode = sock_destroy_inode,...};//至此，与socket有关的文件系统部分初始化完成