drivers/md/dm-zoned.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) 2017 Western Digital Corporation or its affiliates.
  *
  * This file is released under the GPL.
  */

 #ifndef DM_ZONED_H
 #define DM_ZONED_H

 #include <linux/types.h>
 #include <linux/blkdev.h>
 #include <linux/device-mapper.h>
 #include <linux/dm-kcopyd.h>
 #include <linux/list.h>
 #include <linux/spinlock.h>
 #include <linux/mutex.h>
 #include <linux/workqueue.h>
 #include <linux/rwsem.h>
 #include <linux/rbtree.h>
 #include <linux/radix-tree.h>
 #include <linux/shrinker.h>

 /*
  * dm-zoned creates block devices with 4KB blocks, always.
  */
 #define DMZ_BLOCK_SHIFT		12
 #define DMZ_BLOCK_SIZE		(1 << DMZ_BLOCK_SHIFT)
 #define DMZ_BLOCK_MASK		(DMZ_BLOCK_SIZE - 1)

 #define DMZ_BLOCK_SHIFT_BITS	(DMZ_BLOCK_SHIFT + 3)
 #define DMZ_BLOCK_SIZE_BITS	(1 << DMZ_BLOCK_SHIFT_BITS)
 #define DMZ_BLOCK_MASK_BITS	(DMZ_BLOCK_SIZE_BITS - 1)

 #define DMZ_BLOCK_SECTORS_SHIFT	(DMZ_BLOCK_SHIFT - SECTOR_SHIFT)
 #define DMZ_BLOCK_SECTORS	(DMZ_BLOCK_SIZE >> SECTOR_SHIFT)
 #define DMZ_BLOCK_SECTORS_MASK	(DMZ_BLOCK_SECTORS - 1)

 /*
  * 4KB block <-> 512B sector conversion.
  */
 #define dmz_blk2sect(b)		((sector_t)(b) << DMZ_BLOCK_SECTORS_SHIFT)
 #define dmz_sect2blk(s)		((sector_t)(s) >> DMZ_BLOCK_SECTORS_SHIFT)

 #define dmz_bio_block(bio)	dmz_sect2blk((bio)->bi_iter.bi_sector)
 #define dmz_bio_blocks(bio)	dmz_sect2blk(bio_sectors(bio))

 struct dmz_metadata;
 struct dmz_reclaim;

 /*
  * Zoned block device information.
  */
 struct dmz_dev {
 	struct block_device	*bdev;
 	struct dmz_metadata	*metadata;
 	struct dmz_reclaim	*reclaim;

 	char			name[BDEVNAME_SIZE];
 	uuid_t			uuid;

 	sector_t		capacity;

 	unsigned int		dev_idx;

 	unsigned int		nr_zones;
 	unsigned int		zone_offset;

 	unsigned int		flags;

 	sector_t		zone_nr_sectors;

 	unsigned int		nr_rnd;
 	atomic_t		unmap_nr_rnd;
 	struct list_head	unmap_rnd_list;
 	struct list_head	map_rnd_list;

 	unsigned int		nr_seq;
 	atomic_t		unmap_nr_seq;
 	struct list_head	unmap_seq_list;
 	struct list_head	map_seq_list;
 };

 #define dmz_bio_chunk(zmd, bio)	((bio)->bi_iter.bi_sector >> \
 				 dmz_zone_nr_sectors_shift(zmd))
 #define dmz_chunk_block(zmd, b)	((b) & (dmz_zone_nr_blocks(zmd) - 1))

 /* Device flags. */
 #define DMZ_BDEV_DYING		(1 << 0)
 #define DMZ_CHECK_BDEV		(2 << 0)
 #define DMZ_BDEV_REGULAR	(4 << 0)

 /*
  * Zone descriptor.
  */
 struct dm_zone {
 	/* For listing the zone depending on its state */
 	struct list_head	link;

 	/* Device containing this zone */
 	struct dmz_dev		*dev;

 	/* Zone type and state */
 	unsigned long		flags;

 	/* Zone activation reference count */
 	atomic_t		refcount;

 	/* Zone id */
 	unsigned int		id;

 	/* Zone write pointer block (relative to the zone start block) */
 	unsigned int		wp_block;

 	/* Zone weight (number of valid blocks in the zone) */
 	unsigned int		weight;

 	/* The chunk that the zone maps */
 	unsigned int		chunk;

 	/*
 	 * For a sequential data zone, pointer to the random zone
 	 * used as a buffer for processing unaligned writes.
 	 * For a buffer zone, this points back to the data zone.
 	 */
 	struct dm_zone		*bzone;
 };

 /*
  * Zone flags.
  */
 enum {
 	/* Zone write type */
 	DMZ_CACHE,
 	DMZ_RND,
 	DMZ_SEQ,

 	/* Zone critical condition */
 	DMZ_OFFLINE,
 	DMZ_READ_ONLY,

 	/* How the zone is being used */
 	DMZ_META,
 	DMZ_DATA,
 	DMZ_BUF,
 	DMZ_RESERVED,

 	/* Zone internal state */
 	DMZ_RECLAIM,
 	DMZ_SEQ_WRITE_ERR,
 	DMZ_RECLAIM_TERMINATE,
 };

 /*
  * Zone data accessors.
  */
 #define dmz_is_cache(z)		test_bit(DMZ_CACHE, &(z)->flags)
 #define dmz_is_rnd(z)		test_bit(DMZ_RND, &(z)->flags)
 #define dmz_is_seq(z)		test_bit(DMZ_SEQ, &(z)->flags)
 #define dmz_is_empty(z)		((z)->wp_block == 0)
 #define dmz_is_offline(z)	test_bit(DMZ_OFFLINE, &(z)->flags)
 #define dmz_is_readonly(z)	test_bit(DMZ_READ_ONLY, &(z)->flags)
 #define dmz_in_reclaim(z)	test_bit(DMZ_RECLAIM, &(z)->flags)
 #define dmz_is_reserved(z)	test_bit(DMZ_RESERVED, &(z)->flags)
 #define dmz_seq_write_err(z)	test_bit(DMZ_SEQ_WRITE_ERR, &(z)->flags)
 #define dmz_reclaim_should_terminate(z) \
 				test_bit(DMZ_RECLAIM_TERMINATE, &(z)->flags)

 #define dmz_is_meta(z)		test_bit(DMZ_META, &(z)->flags)
 #define dmz_is_buf(z)		test_bit(DMZ_BUF, &(z)->flags)
 #define dmz_is_data(z)		test_bit(DMZ_DATA, &(z)->flags)

 #define dmz_weight(z)		((z)->weight)

 /*
  * Message functions.
  */
 #define dmz_dev_info(dev, format, args...)	\
 	DMINFO("(%s): " format, (dev)->name, ## args)

 #define dmz_dev_err(dev, format, args...)	\
 	DMERR("(%s): " format, (dev)->name, ## args)

 #define dmz_dev_warn(dev, format, args...)	\
 	DMWARN("(%s): " format, (dev)->name, ## args)

 #define dmz_dev_debug(dev, format, args...)	\
 	DMDEBUG("(%s): " format, (dev)->name, ## args)

 /*
  * Functions defined in dm-zoned-metadata.c
  */
 int dmz_ctr_metadata(struct dmz_dev *dev, int num_dev,
 		     struct dmz_metadata **zmd, const char *devname);
 void dmz_dtr_metadata(struct dmz_metadata *zmd);
 int dmz_resume_metadata(struct dmz_metadata *zmd);

 void dmz_lock_map(struct dmz_metadata *zmd);
 void dmz_unlock_map(struct dmz_metadata *zmd);
 void dmz_lock_metadata(struct dmz_metadata *zmd);
 void dmz_unlock_metadata(struct dmz_metadata *zmd);
 void dmz_lock_flush(struct dmz_metadata *zmd);
 void dmz_unlock_flush(struct dmz_metadata *zmd);
 int dmz_flush_metadata(struct dmz_metadata *zmd);
 const char *dmz_metadata_label(struct dmz_metadata *zmd);

 sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone);
 sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone);
 unsigned int dmz_nr_chunks(struct dmz_metadata *zmd);

 bool dmz_check_dev(struct dmz_metadata *zmd);
 bool dmz_dev_is_dying(struct dmz_metadata *zmd);

 #define DMZ_ALLOC_RND		0x01
 #define DMZ_ALLOC_CACHE		0x02
 #define DMZ_ALLOC_SEQ		0x04
 #define DMZ_ALLOC_RECLAIM	0x10

 struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd,
 			       unsigned int dev_idx, unsigned long flags);
 void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone);

 void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *zone,
 		  unsigned int chunk);
 void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
 unsigned int dmz_nr_zones(struct dmz_metadata *zmd);
 unsigned int dmz_nr_cache_zones(struct dmz_metadata *zmd);
 unsigned int dmz_nr_unmap_cache_zones(struct dmz_metadata *zmd);
 unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd, int idx);
 unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd, int idx);
 unsigned int dmz_nr_seq_zones(struct dmz_metadata *zmd, int idx);
 unsigned int dmz_nr_unmap_seq_zones(struct dmz_metadata *zmd, int idx);
 unsigned int dmz_zone_nr_blocks(struct dmz_metadata *zmd);
 unsigned int dmz_zone_nr_blocks_shift(struct dmz_metadata *zmd);
 unsigned int dmz_zone_nr_sectors(struct dmz_metadata *zmd);
 unsigned int dmz_zone_nr_sectors_shift(struct dmz_metadata *zmd);

 /*
  * Activate a zone (increment its reference count).
  */
 static inline void dmz_activate_zone(struct dm_zone *zone)
 {
 	atomic_inc(&zone->refcount);
 }

 int dmz_lock_zone_reclaim(struct dm_zone *zone);
 void dmz_unlock_zone_reclaim(struct dm_zone *zone);
 struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd,
 					 unsigned int dev_idx, bool idle);

 struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd,
 				      unsigned int chunk, int op);
 void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *zone);
 struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd,
 				     struct dm_zone *dzone);

 int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
 			sector_t chunk_block, unsigned int nr_blocks);
 int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
 			  sector_t chunk_block, unsigned int nr_blocks);
 int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone,
 		    sector_t chunk_block);
 int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone,
 			  sector_t *chunk_block);
 int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
 			  struct dm_zone *to_zone);
 int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
 			   struct dm_zone *to_zone, sector_t chunk_block);

 /*
  * Functions defined in dm-zoned-reclaim.c
  */
 int dmz_ctr_reclaim(struct dmz_metadata *zmd, struct dmz_reclaim **zrc, int idx);
 void dmz_dtr_reclaim(struct dmz_reclaim *zrc);
 void dmz_suspend_reclaim(struct dmz_reclaim *zrc);
 void dmz_resume_reclaim(struct dmz_reclaim *zrc);
 void dmz_reclaim_bio_acc(struct dmz_reclaim *zrc);
 void dmz_schedule_reclaim(struct dmz_reclaim *zrc);

 /*
  * Functions defined in dm-zoned-target.c
  */
 bool dmz_bdev_is_dying(struct dmz_dev *dmz_dev);
 bool dmz_check_bdev(struct dmz_dev *dmz_dev);

 /*
  * Deactivate a zone. This decrement the zone reference counter
  * indicating that all BIOs to the zone have completed when the count is 0.
  */
 static inline void dmz_deactivate_zone(struct dm_zone *zone)
 {
 	dmz_reclaim_bio_acc(zone->dev->reclaim);
 	atomic_dec(&zone->refcount);
 }

 /*
  * Test if a zone is active, that is, has a refcount > 0.
  */
 static inline bool dmz_is_active(struct dm_zone *zone)
 {
 	return atomic_read(&zone->refcount);
 }

 #endif /* DM_ZONED_H */
	/* SPDX-License-Identifier: GPL-2.0 */
	/*
	* Copyright (C) 2017 Western Digital Corporation or its affiliates.
	*
	* This file is released under the GPL.
	*/

	#ifndef DM_ZONED_H
	#define DM_ZONED_H

	#include <linux/types.h>
	#include <linux/blkdev.h>
	#include <linux/device-mapper.h>
	#include <linux/dm-kcopyd.h>
	#include <linux/list.h>
	#include <linux/spinlock.h>
	#include <linux/mutex.h>
	#include <linux/workqueue.h>
	#include <linux/rwsem.h>
	#include <linux/rbtree.h>
	#include <linux/radix-tree.h>
	#include <linux/shrinker.h>

	/*
	* dm-zoned creates block devices with 4KB blocks, always.
	*/
	#define DMZ_BLOCK_SHIFT 12
	#define DMZ_BLOCK_SIZE (1 << DMZ_BLOCK_SHIFT)
	#define DMZ_BLOCK_MASK (DMZ_BLOCK_SIZE - 1)

	#define DMZ_BLOCK_SHIFT_BITS (DMZ_BLOCK_SHIFT + 3)
	#define DMZ_BLOCK_SIZE_BITS (1 << DMZ_BLOCK_SHIFT_BITS)
	#define DMZ_BLOCK_MASK_BITS (DMZ_BLOCK_SIZE_BITS - 1)

	#define DMZ_BLOCK_SECTORS_SHIFT (DMZ_BLOCK_SHIFT - SECTOR_SHIFT)
	#define DMZ_BLOCK_SECTORS (DMZ_BLOCK_SIZE >> SECTOR_SHIFT)
	#define DMZ_BLOCK_SECTORS_MASK (DMZ_BLOCK_SECTORS - 1)

	/*
	* 4KB block <-> 512B sector conversion.
	*/
	#define dmz_blk2sect(b) ((sector_t)(b) << DMZ_BLOCK_SECTORS_SHIFT)
	#define dmz_sect2blk(s) ((sector_t)(s) >> DMZ_BLOCK_SECTORS_SHIFT)

	#define dmz_bio_block(bio) dmz_sect2blk((bio)->bi_iter.bi_sector)
	#define dmz_bio_blocks(bio) dmz_sect2blk(bio_sectors(bio))

	struct dmz_metadata;
	struct dmz_reclaim;

	/*
	* Zoned block device information.
	*/
	struct dmz_dev {
	struct block_device *bdev;
	struct dmz_metadata *metadata;
	struct dmz_reclaim *reclaim;

	char name[BDEVNAME_SIZE];
	uuid_t uuid;

	sector_t capacity;

	unsigned int dev_idx;

	unsigned int nr_zones;
	unsigned int zone_offset;

	unsigned int flags;

	sector_t zone_nr_sectors;

	unsigned int nr_rnd;
	atomic_t unmap_nr_rnd;
	struct list_head unmap_rnd_list;
	struct list_head map_rnd_list;

	unsigned int nr_seq;
	atomic_t unmap_nr_seq;
	struct list_head unmap_seq_list;
	struct list_head map_seq_list;
	};

	#define dmz_bio_chunk(zmd, bio) ((bio)->bi_iter.bi_sector >> \
	dmz_zone_nr_sectors_shift(zmd))
	#define dmz_chunk_block(zmd, b) ((b) & (dmz_zone_nr_blocks(zmd) - 1))

	/* Device flags. */
	#define DMZ_BDEV_DYING (1 << 0)
	#define DMZ_CHECK_BDEV (2 << 0)
	#define DMZ_BDEV_REGULAR (4 << 0)

	/*
	* Zone descriptor.
	*/
	struct dm_zone {
	/* For listing the zone depending on its state */
	struct list_head link;

	/* Device containing this zone */
	struct dmz_dev *dev;

	/* Zone type and state */
	unsigned long flags;

	/* Zone activation reference count */
	atomic_t refcount;

	/* Zone id */
	unsigned int id;

	/* Zone write pointer block (relative to the zone start block) */
	unsigned int wp_block;

	/* Zone weight (number of valid blocks in the zone) */
	unsigned int weight;

	/* The chunk that the zone maps */
	unsigned int chunk;

	/*
	* For a sequential data zone, pointer to the random zone
	* used as a buffer for processing unaligned writes.
	* For a buffer zone, this points back to the data zone.
	*/
	struct dm_zone *bzone;
	};

	/*
	* Zone flags.
	*/
	enum {
	/* Zone write type */
	DMZ_CACHE,
	DMZ_RND,
	DMZ_SEQ,

	/* Zone critical condition */
	DMZ_OFFLINE,
	DMZ_READ_ONLY,

	/* How the zone is being used */
	DMZ_META,
	DMZ_DATA,
	DMZ_BUF,
	DMZ_RESERVED,

	/* Zone internal state */
	DMZ_RECLAIM,
	DMZ_SEQ_WRITE_ERR,
	DMZ_RECLAIM_TERMINATE,
	};

	/*
	* Zone data accessors.
	*/
	#define dmz_is_cache(z) test_bit(DMZ_CACHE, &(z)->flags)
	#define dmz_is_rnd(z) test_bit(DMZ_RND, &(z)->flags)
	#define dmz_is_seq(z) test_bit(DMZ_SEQ, &(z)->flags)
	#define dmz_is_empty(z) ((z)->wp_block == 0)
	#define dmz_is_offline(z) test_bit(DMZ_OFFLINE, &(z)->flags)
	#define dmz_is_readonly(z) test_bit(DMZ_READ_ONLY, &(z)->flags)
	#define dmz_in_reclaim(z) test_bit(DMZ_RECLAIM, &(z)->flags)
	#define dmz_is_reserved(z) test_bit(DMZ_RESERVED, &(z)->flags)
	#define dmz_seq_write_err(z) test_bit(DMZ_SEQ_WRITE_ERR, &(z)->flags)
	#define dmz_reclaim_should_terminate(z) \
	test_bit(DMZ_RECLAIM_TERMINATE, &(z)->flags)

	#define dmz_is_meta(z) test_bit(DMZ_META, &(z)->flags)
	#define dmz_is_buf(z) test_bit(DMZ_BUF, &(z)->flags)
	#define dmz_is_data(z) test_bit(DMZ_DATA, &(z)->flags)

	#define dmz_weight(z) ((z)->weight)

	/*
	* Message functions.
	*/
	#define dmz_dev_info(dev, format, args...) \
	DMINFO("(%s): " format, (dev)->name, ## args)

	#define dmz_dev_err(dev, format, args...) \
	DMERR("(%s): " format, (dev)->name, ## args)

	#define dmz_dev_warn(dev, format, args...) \
	DMWARN("(%s): " format, (dev)->name, ## args)

	#define dmz_dev_debug(dev, format, args...) \
	DMDEBUG("(%s): " format, (dev)->name, ## args)

	/*
	* Functions defined in dm-zoned-metadata.c
	*/
	int dmz_ctr_metadata(struct dmz_dev *dev, int num_dev,
	struct dmz_metadata *zmd, const char devname);
	void dmz_dtr_metadata(struct dmz_metadata *zmd);
	int dmz_resume_metadata(struct dmz_metadata *zmd);

	void dmz_lock_map(struct dmz_metadata *zmd);
	void dmz_unlock_map(struct dmz_metadata *zmd);
	void dmz_lock_metadata(struct dmz_metadata *zmd);
	void dmz_unlock_metadata(struct dmz_metadata *zmd);
	void dmz_lock_flush(struct dmz_metadata *zmd);
	void dmz_unlock_flush(struct dmz_metadata *zmd);
	int dmz_flush_metadata(struct dmz_metadata *zmd);
	const char dmz_metadata_label(struct dmz_metadata zmd);

	sector_t dmz_start_sect(struct dmz_metadata zmd, struct dm_zone zone);
	sector_t dmz_start_block(struct dmz_metadata zmd, struct dm_zone zone);
	unsigned int dmz_nr_chunks(struct dmz_metadata *zmd);

	bool dmz_check_dev(struct dmz_metadata *zmd);
	bool dmz_dev_is_dying(struct dmz_metadata *zmd);

	#define DMZ_ALLOC_RND 0x01
	#define DMZ_ALLOC_CACHE 0x02
	#define DMZ_ALLOC_SEQ 0x04
	#define DMZ_ALLOC_RECLAIM 0x10

	struct dm_zone dmz_alloc_zone(struct dmz_metadata zmd,
	unsigned int dev_idx, unsigned long flags);
	void dmz_free_zone(struct dmz_metadata zmd, struct dm_zone zone);

	void dmz_map_zone(struct dmz_metadata zmd, struct dm_zone zone,
	unsigned int chunk);
	void dmz_unmap_zone(struct dmz_metadata zmd, struct dm_zone zone);
	unsigned int dmz_nr_zones(struct dmz_metadata *zmd);
	unsigned int dmz_nr_cache_zones(struct dmz_metadata *zmd);
	unsigned int dmz_nr_unmap_cache_zones(struct dmz_metadata *zmd);
	unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd, int idx);
	unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd, int idx);
	unsigned int dmz_nr_seq_zones(struct dmz_metadata *zmd, int idx);
	unsigned int dmz_nr_unmap_seq_zones(struct dmz_metadata *zmd, int idx);
	unsigned int dmz_zone_nr_blocks(struct dmz_metadata *zmd);
	unsigned int dmz_zone_nr_blocks_shift(struct dmz_metadata *zmd);
	unsigned int dmz_zone_nr_sectors(struct dmz_metadata *zmd);
	unsigned int dmz_zone_nr_sectors_shift(struct dmz_metadata *zmd);

	/*
	* Activate a zone (increment its reference count).
	*/
	static inline void dmz_activate_zone(struct dm_zone *zone)
	{
	atomic_inc(&zone->refcount);
	}

	int dmz_lock_zone_reclaim(struct dm_zone *zone);
	void dmz_unlock_zone_reclaim(struct dm_zone *zone);
	struct dm_zone dmz_get_zone_for_reclaim(struct dmz_metadata zmd,
	unsigned int dev_idx, bool idle);

	struct dm_zone dmz_get_chunk_mapping(struct dmz_metadata zmd,
	unsigned int chunk, int op);
	void dmz_put_chunk_mapping(struct dmz_metadata zmd, struct dm_zone zone);
	struct dm_zone dmz_get_chunk_buffer(struct dmz_metadata zmd,
	struct dm_zone *dzone);

	int dmz_validate_blocks(struct dmz_metadata zmd, struct dm_zone zone,
	sector_t chunk_block, unsigned int nr_blocks);
	int dmz_invalidate_blocks(struct dmz_metadata zmd, struct dm_zone zone,
	sector_t chunk_block, unsigned int nr_blocks);
	int dmz_block_valid(struct dmz_metadata zmd, struct dm_zone zone,
	sector_t chunk_block);
	int dmz_first_valid_block(struct dmz_metadata zmd, struct dm_zone zone,
	sector_t *chunk_block);
	int dmz_copy_valid_blocks(struct dmz_metadata zmd, struct dm_zone from_zone,
	struct dm_zone *to_zone);
	int dmz_merge_valid_blocks(struct dmz_metadata zmd, struct dm_zone from_zone,
	struct dm_zone *to_zone, sector_t chunk_block);

	/*
	* Functions defined in dm-zoned-reclaim.c
	*/
	int dmz_ctr_reclaim(struct dmz_metadata zmd, struct dmz_reclaim *zrc, int idx);
	void dmz_dtr_reclaim(struct dmz_reclaim *zrc);
	void dmz_suspend_reclaim(struct dmz_reclaim *zrc);
	void dmz_resume_reclaim(struct dmz_reclaim *zrc);
	void dmz_reclaim_bio_acc(struct dmz_reclaim *zrc);
	void dmz_schedule_reclaim(struct dmz_reclaim *zrc);

	/*
	* Functions defined in dm-zoned-target.c
	*/
	bool dmz_bdev_is_dying(struct dmz_dev *dmz_dev);
	bool dmz_check_bdev(struct dmz_dev *dmz_dev);

	/*
	* Deactivate a zone. This decrement the zone reference counter
	* indicating that all BIOs to the zone have completed when the count is 0.
	*/
	static inline void dmz_deactivate_zone(struct dm_zone *zone)
	{
	dmz_reclaim_bio_acc(zone->dev->reclaim);
	atomic_dec(&zone->refcount);
	}

	/*
	* Test if a zone is active, that is, has a refcount > 0.
	*/
	static inline bool dmz_is_active(struct dm_zone *zone)
	{
	return atomic_read(&zone->refcount);
	}

	#endif /* DM_ZONED_H */