/*
 * Copyright (c) 2025 Miroslav Cimerman
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup hr
 * @{
 */
/**
 * @file
 */

#ifndef _HR_VAR_H
#define _HR_VAR_H

#include <adt/list.h>
#include <bd_srv.h>
#include <errno.h>
#include <fibril_synch.h>
#include <hr.h>
#include <stdatomic.h>

#include "fge.h"
#include "superblock.h"

#define NAME "hr"
#define HR_STRIP_SIZE DATA_XFER_LIMIT

/*
 * During a rebuild operation, we save the rebuild
 * position this each many bytes. Currently each
 * 10 MiB.
 */
#define HR_REBUILD_SAVE_BYTES (10U * 1024 * 1024)

struct hr_volume;
typedef struct hr_volume hr_volume_t;
typedef struct hr_stripe hr_stripe_t;
typedef struct hr_metadata hr_metadata_t;
typedef struct hr_superblock_ops hr_superblock_ops_t;

typedef struct hr_ops {
	errno_t (*create)(hr_volume_t *);
	errno_t (*init)(hr_volume_t *);
	void (*vol_state_eval)(hr_volume_t *);
	void (*ext_state_cb)(hr_volume_t *, size_t, errno_t);
} hr_ops_t;

typedef struct hr_volume {
	link_t lvolumes; /* link to all volumes list */
	hr_ops_t hr_ops; /* level init and create fcns */
	bd_srvs_t hr_bds; /* block interface to the vol */
	service_id_t svc_id; /* service id */

	list_t range_lock_list; /* list of range locks */
	fibril_mutex_t range_lock_list_lock; /* range locks list lock */

	hr_fpool_t *fge; /* fibril pool */

	void *in_mem_md;
	fibril_mutex_t md_lock; /* lock protecting in_mem_md */

	hr_superblock_ops_t *meta_ops;

	/* invariants */
	size_t extent_no; /* number of extents */
	size_t bsize; /* block size */
	uint64_t truncated_blkno; /* blkno per extent */
	uint64_t data_blkno; /* no. of user usable blocks */
	uint64_t data_offset; /* user data offset in blocks */
	uint32_t strip_size; /* strip size */
	hr_level_t level; /* volume level */
	hr_layout_t layout; /* RAID Level Qualifier */
	char devname[HR_DEVNAME_LEN];

	hr_extent_t extents[HR_MAX_EXTENTS];
	fibril_rwlock_t extents_lock; /* extent service id lock */

	size_t hotspare_no; /* no. of available hotspares */
	hr_extent_t hotspares[HR_MAX_HOTSPARES];
	fibril_mutex_t hotspare_lock; /* lock protecting hotspares */

	fibril_rwlock_t states_lock; /* states lock */

	_Atomic bool state_dirty; /* dirty state */

	/*
	 * used to increment metadata counter on first write,
	 * allowing non-destructive read-only access
	 */
	_Atomic bool first_write;

	_Atomic uint64_t rebuild_blk; /* rebuild position */
	_Atomic int open_cnt; /* open/close() counter */
	hr_vol_state_t state; /* volume state */
	uint8_t vflags;
} hr_volume_t;

typedef enum {
	HR_BD_READ,
	HR_BD_WRITE
} hr_bd_op_type_t;

/* macros for hr_metadata_save() */
#define	WITH_STATE_CALLBACK true
#define	NO_STATE_CALLBACK false

extern errno_t hr_raid0_create(hr_volume_t *);
extern errno_t hr_raid1_create(hr_volume_t *);
extern errno_t hr_raid5_create(hr_volume_t *);

extern errno_t hr_raid0_init(hr_volume_t *);
extern errno_t hr_raid1_init(hr_volume_t *);
extern errno_t hr_raid5_init(hr_volume_t *);

extern void hr_raid0_vol_state_eval(hr_volume_t *);
extern void hr_raid1_vol_state_eval(hr_volume_t *);
extern void hr_raid5_vol_state_eval(hr_volume_t *);

extern void hr_raid0_ext_state_cb(hr_volume_t *, size_t, errno_t);
extern void hr_raid1_ext_state_cb(hr_volume_t *, size_t, errno_t);
extern void hr_raid5_ext_state_cb(hr_volume_t *, size_t, errno_t);
#endif

/** @}
 */