/* SPDX-License-Identifier: GPL-2.0 */

#ifndef BTRFS_ZONED_H
#define BTRFS_ZONED_H

#include <linux/types.h>
#include <linux/atomic.h>
#include <linux/blkdev.h>
#include <linux/blkzoned.h>
#include <linux/errno.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include "messages.h"
#include "volumes.h"
#include "disk-io.h"
#include "block-group.h"
#include "btrfs_inode.h"
#include "fs.h"

struct block_device;
struct extent_buffer;
struct btrfs_bio;
struct btrfs_ordered_extent;
struct btrfs_fs_info;
struct btrfs_space_info;
struct btrfs_eb_write_context;
struct btrfs_fs_devices;

#define BTRFS_DEFAULT_RECLAIM_THRESH           			(75)

struct btrfs_zoned_device_info {
	/*
	 * Number of zones, zone size and types of zones if bdev is a
	 * zoned block device.
	 */
	u64 zone_size;
	u8  zone_size_shift;
	u32 nr_zones;
	unsigned int max_active_zones;
	/*
	 * Reserved active zones for one metadata and one system block group.
	 * It can vary per-device depending on the allocation status.
	 */
	int reserved_active_zones;
	atomic_t active_zones_left;
	unsigned long *seq_zones;
	unsigned long *empty_zones;
	unsigned long *active_zones;
	struct blk_zone *zone_cache;
	struct blk_zone sb_zones[2 * BTRFS_SUPER_MIRROR_MAX];
};

void btrfs_finish_ordered_zoned(struct btrfs_ordered_extent *ordered);

#ifdef CONFIG_BLK_DEV_ZONED
int btrfs_get_dev_zone_info_all_devices(struct btrfs_fs_info *fs_info);
int btrfs_get_dev_zone_info(struct btrfs_device *device, bool populate_cache);
void btrfs_destroy_dev_zone_info(struct btrfs_device *device);
struct btrfs_zoned_device_info *btrfs_clone_dev_zone_info(struct btrfs_device *orig_dev);
int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info);
int btrfs_check_mountopts_zoned(const struct btrfs_fs_info *info, unsigned long *mount_opt);
int btrfs_sb_log_location_bdev(struct block_device *bdev, int mirror, int rw,
			       u64 *bytenr_ret);
int btrfs_sb_log_location(struct btrfs_device *device, int mirror, int rw,
			  u64 *bytenr_ret);
int btrfs_advance_sb_log(struct btrfs_device *device, int mirror);
int btrfs_reset_sb_log_zones(struct block_device *bdev, int mirror);
u64 btrfs_find_allocatable_zones(struct btrfs_device *device, u64 hole_start,
				 u64 hole_end, u64 num_bytes);
int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical,
			    u64 length, u64 *bytes);
int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size);
int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache, bool new);
void btrfs_calc_zone_unusable(struct btrfs_block_group *cache);
bool btrfs_use_zone_append(struct btrfs_bio *bbio);
void btrfs_record_physical_zoned(struct btrfs_bio *bbio);
int btrfs_check_meta_write_pointer(struct btrfs_fs_info *fs_info,
				   struct btrfs_eb_write_context *ctx);
int btrfs_zoned_issue_zeroout(struct btrfs_device *device, u64 physical, u64 length);
int btrfs_sync_zone_write_pointer(struct btrfs_device *tgt_dev, u64 logical,
				  u64 physical_start, u64 physical_pos);
bool btrfs_zone_activate(struct btrfs_block_group *block_group);
int btrfs_zone_finish(struct btrfs_block_group *block_group);
bool btrfs_can_activate_zone(struct btrfs_fs_devices *fs_devices, u64 flags);
void btrfs_zone_finish_endio(struct btrfs_fs_info *fs_info, u64 logical,
			     u64 length);
void btrfs_schedule_zone_finish_bg(struct btrfs_block_group *bg,
				   struct extent_buffer *eb);
void btrfs_clear_data_reloc_bg(struct btrfs_block_group *bg);
void btrfs_free_zone_cache(struct btrfs_fs_info *fs_info);
bool btrfs_zoned_should_reclaim(struct btrfs_fs_info *fs_info);
void btrfs_zoned_release_data_reloc_bg(struct btrfs_fs_info *fs_info, u64 logical,
				       u64 length);
int btrfs_zone_finish_one_bg(struct btrfs_fs_info *fs_info);
int btrfs_zoned_activate_one_bg(struct btrfs_fs_info *fs_info,
				struct btrfs_space_info *space_info, bool do_finish);
void btrfs_check_active_zone_reservation(struct btrfs_fs_info *fs_info);
#else /* CONFIG_BLK_DEV_ZONED */

static inline int btrfs_get_dev_zone_info_all_devices(struct btrfs_fs_info *fs_info)
{
	return 0;
}

static inline int btrfs_get_dev_zone_info(struct btrfs_device *device,
					  bool populate_cache)
{
	return 0;
}

static inline void btrfs_destroy_dev_zone_info(struct btrfs_device *device) { }

/*
 * In case the kernel is compiled without CONFIG_BLK_DEV_ZONED we'll never call
 * into btrfs_clone_dev_zone_info() so it's safe to return NULL here.
 */
static inline struct btrfs_zoned_device_info *btrfs_clone_dev_zone_info(
						 struct btrfs_device *orig_dev)
{
	return NULL;
}

static inline int btrfs_check_zoned_mode(const struct btrfs_fs_info *fs_info)
{
	if (!btrfs_is_zoned(fs_info))
		return 0;

	btrfs_err(fs_info, "zoned block devices support is not enabled");
	return -EOPNOTSUPP;
}

static inline int btrfs_check_mountopts_zoned(const struct btrfs_fs_info *info,
					      unsigned long *mount_opt)
{
	return 0;
}

static inline int btrfs_sb_log_location_bdev(struct block_device *bdev,
					     int mirror, int rw, u64 *bytenr_ret)
{
	*bytenr_ret = btrfs_sb_offset(mirror);
	return 0;
}

static inline int btrfs_sb_log_location(struct btrfs_device *device, int mirror,
					int rw, u64 *bytenr_ret)
{
	*bytenr_ret = btrfs_sb_offset(mirror);
	return 0;
}

static inline int btrfs_advance_sb_log(struct btrfs_device *device, int mirror)
{
	return 0;
}

static inline int btrfs_reset_sb_log_zones(struct block_device *bdev, int mirror)
{
	return 0;
}

static inline u64 btrfs_find_allocatable_zones(struct btrfs_device *device,
					       u64 hole_start, u64 hole_end,
					       u64 num_bytes)
{
	return hole_start;
}

static inline int btrfs_reset_device_zone(struct btrfs_device *device,
					  u64 physical, u64 length, u64 *bytes)
{
	*bytes = 0;
	return 0;
}

static inline int btrfs_ensure_empty_zones(struct btrfs_device *device,
					   u64 start, u64 size)
{
	return 0;
}

static inline int btrfs_load_block_group_zone_info(
		struct btrfs_block_group *cache, bool new)
{
	return 0;
}

static inline void btrfs_calc_zone_unusable(struct btrfs_block_group *cache) { }

static inline bool btrfs_use_zone_append(struct btrfs_bio *bbio)
{
	return false;
}

static inline void btrfs_record_physical_zoned(struct btrfs_bio *bbio)
{
}

static inline int btrfs_check_meta_write_pointer(struct btrfs_fs_info *fs_info,
						 struct btrfs_eb_write_context *ctx)
{
	return 0;
}

static inline int btrfs_zoned_issue_zeroout(struct btrfs_device *device,
					    u64 physical, u64 length)
{
	return -EOPNOTSUPP;
}

static inline int btrfs_sync_zone_write_pointer(struct btrfs_device *tgt_dev,
						u64 logical, u64 physical_start,
						u64 physical_pos)
{
	return -EOPNOTSUPP;
}

static inline bool btrfs_zone_activate(struct btrfs_block_group *block_group)
{
	return true;
}

static inline int btrfs_zone_finish(struct btrfs_block_group *block_group)
{
	return 0;
}

static inline bool btrfs_can_activate_zone(struct btrfs_fs_devices *fs_devices,
					   u64 flags)
{
	return true;
}

static inline void btrfs_zone_finish_endio(struct btrfs_fs_info *fs_info,
					   u64 logical, u64 length) { }

static inline void btrfs_schedule_zone_finish_bg(struct btrfs_block_group *bg,
						 struct extent_buffer *eb) { }

static inline void btrfs_clear_data_reloc_bg(struct btrfs_block_group *bg) { }

static inline void btrfs_free_zone_cache(struct btrfs_fs_info *fs_info) { }

static inline bool btrfs_zoned_should_reclaim(struct btrfs_fs_info *fs_info)
{
	return false;
}

static inline void btrfs_zoned_release_data_reloc_bg(struct btrfs_fs_info *fs_info,
						     u64 logical, u64 length) { }

static inline int btrfs_zone_finish_one_bg(struct btrfs_fs_info *fs_info)
{
	return 1;
}

static inline int btrfs_zoned_activate_one_bg(struct btrfs_fs_info *fs_info,
					      struct btrfs_space_info *space_info,
					      bool do_finish)
{
	/* Consider all the block groups are active */
	return 0;
}

static inline void btrfs_check_active_zone_reservation(struct btrfs_fs_info *fs_info) { }

#endif

static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
{
	struct btrfs_zoned_device_info *zone_info = device->zone_info;

	if (!zone_info)
		return false;

	return test_bit(pos >> zone_info->zone_size_shift, zone_info->seq_zones);
}

static inline bool btrfs_dev_is_empty_zone(struct btrfs_device *device, u64 pos)
{
	struct btrfs_zoned_device_info *zone_info = device->zone_info;

	if (!zone_info)
		return true;

	return test_bit(pos >> zone_info->zone_size_shift, zone_info->empty_zones);
}

static inline void btrfs_dev_set_empty_zone_bit(struct btrfs_device *device,
						u64 pos, bool set)
{
	struct btrfs_zoned_device_info *zone_info = device->zone_info;
	unsigned int zno;

	if (!zone_info)
		return;

	zno = pos >> zone_info->zone_size_shift;
	if (set)
		set_bit(zno, zone_info->empty_zones);
	else
		clear_bit(zno, zone_info->empty_zones);
}

static inline void btrfs_dev_set_zone_empty(struct btrfs_device *device, u64 pos)
{
	btrfs_dev_set_empty_zone_bit(device, pos, true);
}

static inline void btrfs_dev_clear_zone_empty(struct btrfs_device *device, u64 pos)
{
	btrfs_dev_set_empty_zone_bit(device, pos, false);
}

static inline bool btrfs_check_device_zone_type(const struct btrfs_fs_info *fs_info,
						struct block_device *bdev)
{
	if (btrfs_is_zoned(fs_info)) {
		/*
		 * We can allow a regular device on a zoned filesystem, because
		 * we will emulate the zoned capabilities.
		 */
		if (!bdev_is_zoned(bdev))
			return true;

		return fs_info->zone_size ==
			(bdev_zone_sectors(bdev) << SECTOR_SHIFT);
	}

	/* Do not allow Host Managed zoned device. */
	return !bdev_is_zoned(bdev);
}

static inline bool btrfs_check_super_location(struct btrfs_device *device, u64 pos)
{
	/*
	 * On a non-zoned device, any address is OK. On a zoned device,
	 * non-SEQUENTIAL WRITE REQUIRED zones are capable.
	 */
	return device->zone_info == NULL || !btrfs_dev_is_sequential(device, pos);
}

static inline bool btrfs_can_zone_reset(struct btrfs_device *device,
					u64 physical, u64 length)
{
	u64 zone_size;

	if (!btrfs_dev_is_sequential(device, physical))
		return false;

	zone_size = device->zone_info->zone_size;
	if (!IS_ALIGNED(physical, zone_size) || !IS_ALIGNED(length, zone_size))
		return false;

	return true;
}

static inline void btrfs_zoned_meta_io_lock(struct btrfs_fs_info *fs_info)
{
	if (!btrfs_is_zoned(fs_info))
		return;
	mutex_lock(&fs_info->zoned_meta_io_lock);
}

static inline void btrfs_zoned_meta_io_unlock(struct btrfs_fs_info *fs_info)
{
	if (!btrfs_is_zoned(fs_info))
		return;
	mutex_unlock(&fs_info->zoned_meta_io_lock);
}

static inline void btrfs_clear_treelog_bg(struct btrfs_block_group *bg)
{
	struct btrfs_fs_info *fs_info = bg->fs_info;

	if (!btrfs_is_zoned(fs_info))
		return;

	spin_lock(&fs_info->treelog_bg_lock);
	if (fs_info->treelog_bg == bg->start)
		fs_info->treelog_bg = 0;
	spin_unlock(&fs_info->treelog_bg_lock);
}

static inline void btrfs_zoned_data_reloc_lock(struct btrfs_inode *inode)
{
	struct btrfs_root *root = inode->root;

	if (btrfs_is_data_reloc_root(root) && btrfs_is_zoned(root->fs_info))
		mutex_lock(&root->fs_info->zoned_data_reloc_io_lock);
}

static inline void btrfs_zoned_data_reloc_unlock(struct btrfs_inode *inode)
{
	struct btrfs_root *root = inode->root;

	if (btrfs_is_data_reloc_root(root) && btrfs_is_zoned(root->fs_info))
		mutex_unlock(&root->fs_info->zoned_data_reloc_io_lock);
}

static inline bool btrfs_zoned_bg_is_full(const struct btrfs_block_group *bg)
{
	ASSERT(btrfs_is_zoned(bg->fs_info));
	return (bg->alloc_offset == bg->zone_capacity);
}

#endif