内核态下实现mv文件

int rename_file(char *old_filename, char *new_filename)
{
    char *from = old_filename;

    char *to = new_filename;

    int ret = 0;
    struct nameidata old_nd, new_nd;
    struct dentry *old_dentry, *new_dentry;

    ret = path_lookup(from, LOOKUP_PARENT, &old_nd);

    if (ret != 0)
    {
         return -ENOENT;
    }

    ret = path_lookup(to,LOOKUP_PARENT, &new_nd);
    if (ret != 0)
    {
         return -ENOENT;
    }

    old_dentry = lookup_one_len(old_nd.last.name, old_nd.path.dentry, strlen(old_nd.last.name));
    if (IS_ERR(old_dentry))
    {
          //path_release(&nd);
          return -EACCES;
    }

    

    new_dentry = lookup_one_len(new_nd.last.name, new_nd.path.dentry, strlen(new_nd.last.name));
    if (IS_ERR(new_dentry))
    {
          //path_release(&new_nd);
          return -EACCES;
    }

    vfs_rename(old_nd.path.dentry->d_inode, old_dentry, new_nd.path.dentry->d_inode, new_dentry);

   dput(old_dentry);

   dput(new_dentry);
//path_release(&nd);

   return 0;
   
}

先这么实现内核态下的文件移动吧