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 unsigned long es_stats_cache_hits; 74 unsigned long 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 int 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 int 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 struct extent_status *es); 144 extern bool ext4_es_scan_range(struct inode *inode, 145 int (*matching_fn)(struct extent_status *es), 146 ext4_lblk_t lblk, ext4_lblk_t end); 147 extern bool ext4_es_scan_clu(struct inode *inode, 148 int (*matching_fn)(struct extent_status *es), 149 ext4_lblk_t lblk); 150 151 static inline unsigned int ext4_es_status(struct extent_status *es) 152 { 153 return es->es_pblk >> ES_SHIFT; 154 } 155 156 static inline unsigned int ext4_es_type(struct extent_status *es) 157 { 158 return (es->es_pblk & ES_TYPE_MASK) >> ES_SHIFT; 159 } 160 161 static inline int ext4_es_is_written(struct extent_status *es) 162 { 163 return (ext4_es_type(es) & EXTENT_STATUS_WRITTEN) != 0; 164 } 165 166 static inline int ext4_es_is_unwritten(struct extent_status *es) 167 { 168 return (ext4_es_type(es) & EXTENT_STATUS_UNWRITTEN) != 0; 169 } 170 171 static inline int ext4_es_is_delayed(struct extent_status *es) 172 { 173 return (ext4_es_type(es) & EXTENT_STATUS_DELAYED) != 0; 174 } 175 176 static inline int ext4_es_is_hole(struct extent_status *es) 177 { 178 return (ext4_es_type(es) & EXTENT_STATUS_HOLE) != 0; 179 } 180 181 static inline int ext4_es_is_mapped(struct extent_status *es) 182 { 183 return (ext4_es_is_written(es) || ext4_es_is_unwritten(es)); 184 } 185 186 static inline int ext4_es_is_delonly(struct extent_status *es) 187 { 188 return (ext4_es_is_delayed(es) && !ext4_es_is_unwritten(es)); 189 } 190 191 static inline void ext4_es_set_referenced(struct extent_status *es) 192 { 193 es->es_pblk |= ((ext4_fsblk_t)EXTENT_STATUS_REFERENCED) << ES_SHIFT; 194 } 195 196 static inline void ext4_es_clear_referenced(struct extent_status *es) 197 { 198 es->es_pblk &= ~(((ext4_fsblk_t)EXTENT_STATUS_REFERENCED) << ES_SHIFT); 199 } 200 201 static inline int ext4_es_is_referenced(struct extent_status *es) 202 { 203 return (ext4_es_status(es) & EXTENT_STATUS_REFERENCED) != 0; 204 } 205 206 static inline ext4_fsblk_t ext4_es_pblock(struct extent_status *es) 207 { 208 return es->es_pblk & ~ES_MASK; 209 } 210 211 static inline void ext4_es_store_pblock(struct extent_status *es, 212 ext4_fsblk_t pb) 213 { 214 ext4_fsblk_t block; 215 216 block = (pb & ~ES_MASK) | (es->es_pblk & ES_MASK); 217 es->es_pblk = block; 218 } 219 220 static inline void ext4_es_store_status(struct extent_status *es, 221 unsigned int status) 222 { 223 es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) | 224 (es->es_pblk & ~ES_MASK); 225 } 226 227 static inline void ext4_es_store_pblock_status(struct extent_status *es, 228 ext4_fsblk_t pb, 229 unsigned int status) 230 { 231 es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) | 232 (pb & ~ES_MASK); 233 } 234 235 extern int ext4_es_register_shrinker(struct ext4_sb_info *sbi); 236 extern void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi); 237 238 extern int ext4_seq_es_shrinker_info_show(struct seq_file *seq, void *v); 239 240 extern int __init ext4_init_pending(void); 241 extern void ext4_exit_pending(void); 242 extern void ext4_init_pending_tree(struct ext4_pending_tree *tree); 243 extern void ext4_remove_pending(struct inode *inode, ext4_lblk_t lblk); 244 extern bool ext4_is_pending(struct inode *inode, ext4_lblk_t lblk); 245 extern int ext4_es_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk, 246 bool allocated); 247 extern unsigned int ext4_es_delayed_clu(struct inode *inode, ext4_lblk_t lblk, 248 ext4_lblk_t len); 249 extern void ext4_es_remove_blks(struct inode *inode, ext4_lblk_t lblk, 250 ext4_lblk_t len); 251 252 #endif /* _EXT4_EXTENTS_STATUS_H */ 253