[文件系统] 一个简单文件系统的实现（8）

普通文件操作(在file.c中定义)，只需要实现一个gt_sync_file

const struct file_operations gt_file_operations ={
        .llseek                =generic_file_llseek,
        .read                =do_sync_read,
        .write                =do_sync_write,
        .aio_read        =generic_file_aio_read,
        .aio_write        =generic_file_aio_write,
        .mmap                =generic_file_mmap,
        .open                =generic_file_open,
        .fsync                =gt_sync_file,
};

来看看gt_sync_file(在file.c中定义)

int gt_sync_file(struct file *file,struct dentry *dentry,int datasync){
        struct inode *inode =dentry->d_inode;
        int err,ret;
        ret=sync_mapping_buffers(inode->i_mapping);
        if(!(inode->i_state&I_DIRTY))
                return ret;
        if(datasync && !(inode->i_state&I_DIRTY_DATASYNC))
                return ret;
        err=gt_sync_inode(inode);
        if(ret==)
                ret=err;
        return ret;
}

函数调用gt_sync_inode(在inode.c中定义)

int gt_sync_inode(struct inode *inode){
        int ret=;
        struct buffer_head *bh;
        bh=gt_update_inode(inode);//获取到磁盘索引节点所在的缓冲区
        if(bh && buffer_dirty(bh)){//如果为脏，则同步
                sync_dirty_buffer(bh);
                if(buffer_req(bh)&&!buffer_uptodate(bh)){
                        printk("IO error syncing gt inode\n");
                        ret=-1;
                }
        }else if(!bh)
                ret=-1;
        brelse(bh);
        return ret;
}

文章来源CU社区：[文件系统] 一个简单文件系统的实现