1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2009 Oracle.  All rights reserved.
4 */
5
6#ifndef BTRFS_FREE_SPACE_CACHE_H
7#define BTRFS_FREE_SPACE_CACHE_H
8
9#include <linux/rbtree.h>
10#include <linux/list.h>
11#include <linux/spinlock.h>
12#include <linux/mutex.h>
13#include "fs.h"
14
15struct inode;
16struct page;
17struct btrfs_fs_info;
18struct btrfs_path;
19struct btrfs_trans_handle;
20struct btrfs_trim_block_group;
21
22/*
23 * This is the trim state of an extent or bitmap.
24 *
25 * BTRFS_TRIM_STATE_TRIMMING is special and used to maintain the state of a
26 * bitmap as we may need several trims to fully trim a single bitmap entry.
27 * This is reset should any free space other than trimmed space be added to the
28 * bitmap.
29 */
30enum btrfs_trim_state {
31	BTRFS_TRIM_STATE_UNTRIMMED,
32	BTRFS_TRIM_STATE_TRIMMED,
33	BTRFS_TRIM_STATE_TRIMMING,
34};
35
36struct btrfs_free_space {
37	struct rb_node offset_index;
38	struct rb_node bytes_index;
39	u64 offset;
40	u64 bytes;
41	u64 max_extent_size;
42	unsigned long *bitmap;
43	struct list_head list;
44	enum btrfs_trim_state trim_state;
45	s32 bitmap_extents;
46};
47
48static inline bool btrfs_free_space_trimmed(struct btrfs_free_space *info)
49{
50	return (info->trim_state == BTRFS_TRIM_STATE_TRIMMED);
51}
52
53static inline bool btrfs_free_space_trimming_bitmap(
54					    struct btrfs_free_space *info)
55{
56	return (info->trim_state == BTRFS_TRIM_STATE_TRIMMING);
57}
58
59/*
60 * Deltas are an effective way to populate global statistics.  Give macro names
61 * to make it clear what we're doing.  An example is discard_extents in
62 * btrfs_free_space_ctl.
63 */
64enum {
65	BTRFS_STAT_CURR,
66	BTRFS_STAT_PREV,
67	BTRFS_STAT_NR_ENTRIES,
68};
69
70struct btrfs_free_space_ctl {
71	spinlock_t tree_lock;
72	struct rb_root free_space_offset;
73	struct rb_root_cached free_space_bytes;
74	u64 free_space;
75	int extents_thresh;
76	int free_extents;
77	int total_bitmaps;
78	int unit;
79	u64 start;
80	s32 discardable_extents[BTRFS_STAT_NR_ENTRIES];
81	s64 discardable_bytes[BTRFS_STAT_NR_ENTRIES];
82	const struct btrfs_free_space_op *op;
83	struct btrfs_block_group *block_group;
84	struct mutex cache_writeout_mutex;
85	struct list_head trimming_ranges;
86};
87
88struct btrfs_free_space_op {
89	bool (*use_bitmap)(struct btrfs_free_space_ctl *ctl,
90			   struct btrfs_free_space *info);
91};
92
93struct btrfs_io_ctl {
94	void *cur, *orig;
95	struct page *page;
96	struct page **pages;
97	struct btrfs_fs_info *fs_info;
98	struct inode *inode;
99	unsigned long size;
100	int index;
101	int num_pages;
102	int entries;
103	int bitmaps;
104};
105
106int __init btrfs_free_space_init(void);
107void __cold btrfs_free_space_exit(void);
108struct inode *lookup_free_space_inode(struct btrfs_block_group *block_group,
109		struct btrfs_path *path);
110int create_free_space_inode(struct btrfs_trans_handle *trans,
111			    struct btrfs_block_group *block_group,
112			    struct btrfs_path *path);
113int btrfs_remove_free_space_inode(struct btrfs_trans_handle *trans,
114				  struct inode *inode,
115				  struct btrfs_block_group *block_group);
116
117int btrfs_truncate_free_space_cache(struct btrfs_trans_handle *trans,
118				    struct btrfs_block_group *block_group,
119				    struct inode *inode);
120int load_free_space_cache(struct btrfs_block_group *block_group);
121int btrfs_wait_cache_io(struct btrfs_trans_handle *trans,
122			struct btrfs_block_group *block_group,
123			struct btrfs_path *path);
124int btrfs_write_out_cache(struct btrfs_trans_handle *trans,
125			  struct btrfs_block_group *block_group,
126			  struct btrfs_path *path);
127
128void btrfs_init_free_space_ctl(struct btrfs_block_group *block_group,
129			       struct btrfs_free_space_ctl *ctl);
130int btrfs_add_free_space(struct btrfs_block_group *block_group,
131			 u64 bytenr, u64 size);
132int btrfs_add_free_space_unused(struct btrfs_block_group *block_group,
133				u64 bytenr, u64 size);
134int btrfs_add_free_space_async_trimmed(struct btrfs_block_group *block_group,
135				       u64 bytenr, u64 size);
136int btrfs_remove_free_space(struct btrfs_block_group *block_group,
137			    u64 bytenr, u64 size);
138void btrfs_remove_free_space_cache(struct btrfs_block_group *block_group);
139bool btrfs_is_free_space_trimmed(struct btrfs_block_group *block_group);
140u64 btrfs_find_space_for_alloc(struct btrfs_block_group *block_group,
141			       u64 offset, u64 bytes, u64 empty_size,
142			       u64 *max_extent_size);
143void btrfs_dump_free_space(struct btrfs_block_group *block_group,
144			   u64 bytes);
145int btrfs_find_space_cluster(struct btrfs_block_group *block_group,
146			     struct btrfs_free_cluster *cluster,
147			     u64 offset, u64 bytes, u64 empty_size);
148void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster);
149u64 btrfs_alloc_from_cluster(struct btrfs_block_group *block_group,
150			     struct btrfs_free_cluster *cluster, u64 bytes,
151			     u64 min_start, u64 *max_extent_size);
152void btrfs_return_cluster_to_free_space(
153			       struct btrfs_block_group *block_group,
154			       struct btrfs_free_cluster *cluster);
155int btrfs_trim_block_group(struct btrfs_block_group *block_group,
156			   u64 *trimmed, u64 start, u64 end, u64 minlen);
157int btrfs_trim_block_group_extents(struct btrfs_block_group *block_group,
158				   u64 *trimmed, u64 start, u64 end, u64 minlen,
159				   bool async);
160int btrfs_trim_block_group_bitmaps(struct btrfs_block_group *block_group,
161				   u64 *trimmed, u64 start, u64 end, u64 minlen,
162				   u64 maxlen, bool async);
163
164bool btrfs_free_space_cache_v1_active(struct btrfs_fs_info *fs_info);
165int btrfs_set_free_space_cache_v1_active(struct btrfs_fs_info *fs_info, bool active);
166/* Support functions for running our sanity tests */
167#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
168int test_add_free_space_entry(struct btrfs_block_group *cache,
169			      u64 offset, u64 bytes, bool bitmap);
170int test_check_exists(struct btrfs_block_group *cache, u64 offset, u64 bytes);
171#endif
172
173#endif
174