/* SPDX-License-Identifier: GPL-2.0-only *//* * Copyright (C) 2011 Red Hat, Inc. * * This file is released under the GPL. */ #ifndef DM_SPACE_MAP_COMMON_H#define DM_SPACE_MAP_COMMON_H #include "dm-btree.h" /*----------------------------------------------------------------*/ /* * Low level disk format * * Bitmap btree * ------------ * * Each value stored in the btree is an index_entry.  This points to a * block that is used as a bitmap.  Within the bitmap hold 2 bits per * entry, which represent UNUSED = 0, REF_COUNT = 1, REF_COUNT = 2 and * REF_COUNT = many. * * Refcount btree * -------------- * * Any entry that has a ref count higher than 2 gets entered in the ref * count tree.  The leaf values for this tree is the 32-bit ref count. */ struct disk_index_entry {	__le64 blocknr;	__le32 nr_free;	__le32 none_free_before;} __packed __aligned(8);  #define MAX_METADATA_BITMAPS 255struct disk_metadata_index {	__le32 csum;	__le32 padding;	__le64 blocknr; 	struct disk_index_entry index[MAX_METADATA_BITMAPS];} __packed __aligned(8); struct ll_disk; typedef int (*load_ie_fn)(struct ll_disk *ll, dm_block_t index, struct disk_index_entry *result);typedef int (*save_ie_fn)(struct ll_disk *ll, dm_block_t index, struct disk_index_entry *ie);typedef int (*init_index_fn)(struct ll_disk *ll);typedef int (*open_index_fn)(struct ll_disk *ll);typedef dm_block_t (*max_index_entries_fn)(struct ll_disk *ll);typedef int (*commit_fn)(struct ll_disk *ll); /* * A lot of time can be wasted reading and writing the same * index entry.  So we cache a few entries. */#define IE_CACHE_SIZE 64#define IE_CACHE_MASK (IE_CACHE_SIZE - 1) struct ie_cache {	bool valid;	bool dirty;	dm_block_t index;	struct disk_index_entry ie;}; struct ll_disk {	struct dm_transaction_manager *tm;	struct dm_btree_info bitmap_info;	struct dm_btree_info ref_count_info; 	uint32_t block_size;	uint32_t entries_per_block;	dm_block_t nr_blocks;	dm_block_t nr_allocated; 	/*	 * bitmap_root may be a btree root or a simple index.	 */	dm_block_t bitmap_root; 	dm_block_t ref_count_root; 	struct disk_metadata_index mi_le;	load_ie_fn load_ie;	save_ie_fn save_ie;	init_index_fn init_index;	open_index_fn open_index;	max_index_entries_fn max_entries;	commit_fn commit;	bool bitmap_index_changed:1; 	struct ie_cache ie_cache[IE_CACHE_SIZE];}; struct disk_sm_root {	__le64 nr_blocks;	__le64 nr_allocated;	__le64 bitmap_root;	__le64 ref_count_root;} __packed __aligned(8); #define ENTRIES_PER_BYTE 4 struct disk_bitmap_header {	__le32 csum;	__le32 not_used;	__le64 blocknr;} __packed __aligned(8); /*----------------------------------------------------------------*/ int sm_ll_extend(struct ll_disk *ll, dm_block_t extra_blocks);int sm_ll_lookup_bitmap(struct ll_disk *ll, dm_block_t b, uint32_t *result);int sm_ll_lookup(struct ll_disk *ll, dm_block_t b, uint32_t *result);int sm_ll_find_free_block(struct ll_disk *ll, dm_block_t begin,			  dm_block_t end, dm_block_t *result);int sm_ll_find_common_free_block(struct ll_disk *old_ll, struct ll_disk *new_ll,				 dm_block_t begin, dm_block_t end, dm_block_t *result); /* * The next three functions return (via nr_allocations) the net number of * allocations that were made.  This number may be negative if there were * more frees than allocs. */int sm_ll_insert(struct ll_disk *ll, dm_block_t b, uint32_t ref_count, int32_t *nr_allocations);int sm_ll_inc(struct ll_disk *ll, dm_block_t b, dm_block_t e, int32_t *nr_allocations);int sm_ll_dec(struct ll_disk *ll, dm_block_t b, dm_block_t e, int32_t *nr_allocations);int sm_ll_commit(struct ll_disk *ll); int sm_ll_new_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm);int sm_ll_open_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm,			void *root_le, size_t len); int sm_ll_new_disk(struct ll_disk *ll, struct dm_transaction_manager *tm);int sm_ll_open_disk(struct ll_disk *ll, struct dm_transaction_manager *tm,		    void *root_le, size_t len); /*----------------------------------------------------------------*/ #endif	/* DM_SPACE_MAP_COMMON_H */