overlay_vbd.h

#ifndef __OVERLAY_VBD_H__
#define __OVERLAY_VBD_H__

#undef __KERNEL__
#ifndef HBDEBUG
#define HBDEBUG (1)
#endif

#include <linux/kthread.h>
#include <linux/blk-mq.h>

struct lsmt_file;
/*
 * Each block ovbd device has a radix_tree ovbd_pages of pages that stores
 * the pages containing the block device's contents. A ovbd page's ->index is
 * its offset in PAGE_SIZE units. This is similar to, but in no way connected
 * with, the kernel's pagecache or buffer cache (which sit above our block
 * device).
 */
struct ovbd_device {
	int		ovbd_number;

	struct request_queue	*ovbd_queue;
	struct gendisk		*ovbd_disk;
	struct list_head	ovbd_list;

	/*
	 * Backing store of pages and lock to protect it. This is the contents
	 * of the block device.
	 */
	// spinlock_t		ovbd_lock;
	// struct radix_tree_root	ovbd_pages;

	uint16_t block_size;

        // block-dev provides data by
        // using `lsmtfile_read`
        // assume block-dev size is `lsmtfile_len`
	struct lsmt_file* fp;
 	unsigned char* path;

	struct kthread_worker	worker;
	struct task_struct	*worker_task;

        struct blk_mq_tag_set	tag_set;
	// bool initialized ;

};

struct ovbd_cmd {
        struct kthread_work work;
        long ret;
        struct kiocb iocb;
        struct bio_vec *bvec;
};

#endif