1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * fs/ext4/extents_status.h
4 *
5 * Written by Yongqiang Yang <xiaoqiangnk@gmail.com>
6 * Modified by
7 * Allison Henderson <achender@linux.vnet.ibm.com>
8 * Zheng Liu <wenqing.lz@taobao.com>
9 *
10 */
11
12 #ifndef _EXT4_EXTENTS_STATUS_H
13 #define _EXT4_EXTENTS_STATUS_H
14
15 /*
16 * Turn on ES_DEBUG__ to get lots of info about extent status operations.
17 */
18 #ifdef ES_DEBUG__
19 #define es_debug(fmt, ...) printk(fmt, ##__VA_ARGS__)
20 #else
21 #define es_debug(fmt, ...) no_printk(fmt, ##__VA_ARGS__)
22 #endif
23
24 /*
25 * With ES_AGGRESSIVE_TEST defined, the result of es caching will be
26 * checked with old map_block's result.
27 */
28 #define ES_AGGRESSIVE_TEST__
29
30 /*
31 * These flags live in the high bits of extent_status.es_pblk
32 */
33 enum {
34 ES_WRITTEN_B,
35 ES_UNWRITTEN_B,
36 ES_DELAYED_B,
37 ES_HOLE_B,
38 ES_REFERENCED_B,
39 ES_FLAGS
40 };
41
42 #define ES_SHIFT (sizeof(ext4_fsblk_t)*8 - ES_FLAGS)
43 #define ES_MASK (~((ext4_fsblk_t)0) << ES_SHIFT)
44
45 #define EXTENT_STATUS_WRITTEN (1 << ES_WRITTEN_B)
46 #define EXTENT_STATUS_UNWRITTEN (1 << ES_UNWRITTEN_B)
47 #define EXTENT_STATUS_DELAYED (1 << ES_DELAYED_B)
48 #define EXTENT_STATUS_HOLE (1 << ES_HOLE_B)
49 #define EXTENT_STATUS_REFERENCED (1 << ES_REFERENCED_B)
50
51 #define ES_TYPE_MASK ((ext4_fsblk_t)(EXTENT_STATUS_WRITTEN | \
52 EXTENT_STATUS_UNWRITTEN | \
53 EXTENT_STATUS_DELAYED | \
54 EXTENT_STATUS_HOLE) << ES_SHIFT)
55
56 struct ext4_sb_info;
57 struct ext4_extent;
58
59 struct extent_status {
60 struct rb_node rb_node;
61 ext4_lblk_t es_lblk; /* first logical block extent covers */
62 ext4_lblk_t es_len; /* length of extent in block */
63 ext4_fsblk_t es_pblk; /* first physical block */
64 };
65
66 struct ext4_es_tree {
67 struct rb_root root;
68 struct extent_status *cache_es; /* recently accessed extent */
69 };
70
71 struct ext4_es_stats {
72 unsigned long es_stats_shrunk;
73 struct percpu_counter es_stats_cache_hits;
74 struct percpu_counter es_stats_cache_misses;
75 u64 es_stats_scan_time;
76 u64 es_stats_max_scan_time;
77 struct percpu_counter es_stats_all_cnt;
78 struct percpu_counter es_stats_shk_cnt;
79 };
80
81 /*
82 * Pending cluster reservations for bigalloc file systems
83 *
84 * A cluster with a pending reservation is a logical cluster shared by at
85 * least one extent in the extents status tree with delayed and unwritten
86 * status and at least one other written or unwritten extent. The
87 * reservation is said to be pending because a cluster reservation would
88 * have to be taken in the event all blocks in the cluster shared with
89 * written or unwritten extents were deleted while the delayed and
90 * unwritten blocks remained.
91 *
92 * The set of pending cluster reservations is an auxiliary data structure
93 * used with the extents status tree to implement reserved cluster/block
94 * accounting for bigalloc file systems. The set is kept in memory and
95 * records all pending cluster reservations.
96 *
97 * Its primary function is to avoid the need to read extents from the
98 * disk when invalidating pages as a result of a truncate, punch hole, or
99 * collapse range operation. Page invalidation requires a decrease in the
100 * reserved cluster count if it results in the removal of all delayed
101 * and unwritten extents (blocks) from a cluster that is not shared with a
102 * written or unwritten extent, and no decrease otherwise. Determining
103 * whether the cluster is shared can be done by searching for a pending
104 * reservation on it.
105 *
106 * Secondarily, it provides a potentially faster method for determining
107 * whether the reserved cluster count should be increased when a physical
108 * cluster is deallocated as a result of a truncate, punch hole, or
109 * collapse range operation. The necessary information is also present
110 * in the extents status tree, but might be more rapidly accessed in
111 * the pending reservation set in many cases due to smaller size.
112 *
113 * The pending cluster reservation set is implemented as a red-black tree
114 * with the goal of minimizing per page search time overhead.
115 */
116
117 struct pending_reservation {
118 struct rb_node rb_node;
119 ext4_lblk_t lclu;
120 };
121
122 struct ext4_pending_tree {
123 struct rb_root root;
124 };
125
126 extern int __init ext4_init_es(void);
127 extern void ext4_exit_es(void);
128 extern void ext4_es_init_tree(struct ext4_es_tree *tree);
129
130 extern void ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
131 ext4_lblk_t len, ext4_fsblk_t pblk,
132 unsigned int status);
133 extern void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk,
134 ext4_lblk_t len, ext4_fsblk_t pblk,
135 unsigned int status);
136 extern void ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
137 ext4_lblk_t len);
138 extern void ext4_es_find_extent_range(struct inode *inode,
139 int (*match_fn)(struct extent_status *es),
140 ext4_lblk_t lblk, ext4_lblk_t end,
141 struct extent_status *es);
142 extern int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
143 ext4_lblk_t *next_lblk,
144 struct extent_status *es);
145 extern bool ext4_es_scan_range(struct inode *inode,
146 int (*matching_fn)(struct extent_status *es),
147 ext4_lblk_t lblk, ext4_lblk_t end);
148 extern bool ext4_es_scan_clu(struct inode *inode,
149 int (*matching_fn)(struct extent_status *es),
150 ext4_lblk_t lblk);
151
152 static inline unsigned int ext4_es_status(struct extent_status *es)
153 {
154 return es->es_pblk >> ES_SHIFT;
155 }
156
157 static inline unsigned int ext4_es_type(struct extent_status *es)
158 {
159 return (es->es_pblk & ES_TYPE_MASK) >> ES_SHIFT;
160 }
161
162 static inline int ext4_es_is_written(struct extent_status *es)
163 {
164 return (ext4_es_type(es) & EXTENT_STATUS_WRITTEN) != 0;
165 }
166
167 static inline int ext4_es_is_unwritten(struct extent_status *es)
168 {
169 return (ext4_es_type(es) & EXTENT_STATUS_UNWRITTEN) != 0;
170 }
171
172 static inline int ext4_es_is_delayed(struct extent_status *es)
173 {
174 return (ext4_es_type(es) & EXTENT_STATUS_DELAYED) != 0;
175 }
176
177 static inline int ext4_es_is_hole(struct extent_status *es)
178 {
179 return (ext4_es_type(es) & EXTENT_STATUS_HOLE) != 0;
180 }
181
182 static inline int ext4_es_is_mapped(struct extent_status *es)
183 {
184 return (ext4_es_is_written(es) || ext4_es_is_unwritten(es));
185 }
186
187 static inline int ext4_es_is_delonly(struct extent_status *es)
188 {
189 return (ext4_es_is_delayed(es) && !ext4_es_is_unwritten(es));
190 }
191
192 static inline void ext4_es_set_referenced(struct extent_status *es)
193 {
194 es->es_pblk |= ((ext4_fsblk_t)EXTENT_STATUS_REFERENCED) << ES_SHIFT;
195 }
196
197 static inline void ext4_es_clear_referenced(struct extent_status *es)
198 {
199 es->es_pblk &= ~(((ext4_fsblk_t)EXTENT_STATUS_REFERENCED) << ES_SHIFT);
200 }
201
202 static inline int ext4_es_is_referenced(struct extent_status *es)
203 {
204 return (ext4_es_status(es) & EXTENT_STATUS_REFERENCED) != 0;
205 }
206
207 static inline ext4_fsblk_t ext4_es_pblock(struct extent_status *es)
208 {
209 return es->es_pblk & ~ES_MASK;
210 }
211
212 static inline ext4_fsblk_t ext4_es_show_pblock(struct extent_status *es)
213 {
214 ext4_fsblk_t pblock = ext4_es_pblock(es);
215 return pblock == ~ES_MASK ? 0 : pblock;
216 }
217
218 static inline void ext4_es_store_pblock(struct extent_status *es,
219 ext4_fsblk_t pb)
220 {
221 ext4_fsblk_t block;
222
223 block = (pb & ~ES_MASK) | (es->es_pblk & ES_MASK);
224 es->es_pblk = block;
225 }
226
227 static inline void ext4_es_store_status(struct extent_status *es,
228 unsigned int status)
229 {
230 es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) |
231 (es->es_pblk & ~ES_MASK);
232 }
233
234 static inline void ext4_es_store_pblock_status(struct extent_status *es,
235 ext4_fsblk_t pb,
236 unsigned int status)
237 {
238 es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) |
239 (pb & ~ES_MASK);
240 }
241
242 extern int ext4_es_register_shrinker(struct ext4_sb_info *sbi);
243 extern void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi);
244
245 extern int ext4_seq_es_shrinker_info_show(struct seq_file *seq, void *v);
246
247 extern int __init ext4_init_pending(void);
248 extern void ext4_exit_pending(void);
249 extern void ext4_init_pending_tree(struct ext4_pending_tree *tree);
250 extern void ext4_remove_pending(struct inode *inode, ext4_lblk_t lblk);
251 extern bool ext4_is_pending(struct inode *inode, ext4_lblk_t lblk);
252 extern void ext4_es_insert_delayed_extent(struct inode *inode, ext4_lblk_t lblk,
253 ext4_lblk_t len, bool lclu_allocated,
254 bool end_allocated);
255 extern unsigned int ext4_es_delayed_clu(struct inode *inode, ext4_lblk_t lblk,
256 ext4_lblk_t len);
257 extern void ext4_clear_inode_es(struct inode *inode);
258
259 #endif /* _EXT4_EXTENTS_STATUS_H */
260
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