fs/ext4/extents_status.h

   1 /*
   2  *  fs/ext4/extents_status.h
   3  *
   4  * Written by Yongqiang Yang <xiaoqiangnk@gmail.com>
   5  * Modified by
   6  *      Allison Henderson <achender@linux.vnet.ibm.com>
   7  *      Zheng Liu <wenqing.lz@taobao.com>
   8  *
   9  */
  10
  11 #ifndef _EXT4_EXTENTS_STATUS_H
  12 #define _EXT4_EXTENTS_STATUS_H
  13
  14 /*
  15  * Turn on ES_DEBUG__ to get lots of info about extent status operations.
  16  */
  17 #ifdef ES_DEBUG__
  18 #define es_debug(fmt, ...)      printk(fmt, ##__VA_ARGS__)
  19 #else
  20 #define es_debug(fmt, ...)      no_printk(fmt, ##__VA_ARGS__)
  21 #endif
  22
  23 /*
  24  * With ES_AGGRESSIVE_TEST defined, the result of es caching will be
  25  * checked with old map_block's result.
  26  */
  27 #define ES_AGGRESSIVE_TEST__
  28
  29 /*
  30  * These flags live in the high bits of extent_status.es_pblk
  31  */
  32 enum {
  33         ES_WRITTEN_B,
  34         ES_UNWRITTEN_B,
  35         ES_DELAYED_B,
  36         ES_HOLE_B,
  37         ES_REFERENCED_B,
  38         ES_FLAGS
  39 };
  40
  41 #define ES_SHIFT (sizeof(ext4_fsblk_t)*8 - ES_FLAGS)
  42 #define ES_MASK (~((ext4_fsblk_t)0) << ES_SHIFT)
  43
  44 #define EXTENT_STATUS_WRITTEN   (1 << ES_WRITTEN_B)
  45 #define EXTENT_STATUS_UNWRITTEN (1 << ES_UNWRITTEN_B)
  46 #define EXTENT_STATUS_DELAYED   (1 << ES_DELAYED_B)
  47 #define EXTENT_STATUS_HOLE      (1 << ES_HOLE_B)
  48 #define EXTENT_STATUS_REFERENCED        (1 << ES_REFERENCED_B)
  49
  50 #define ES_TYPE_MASK    ((ext4_fsblk_t)(EXTENT_STATUS_WRITTEN | \
  51                           EXTENT_STATUS_UNWRITTEN | \
  52                           EXTENT_STATUS_DELAYED | \
  53                           EXTENT_STATUS_HOLE) << ES_SHIFT)
  54
  55 struct ext4_sb_info;
  56 struct ext4_extent;
  57
  58 struct extent_status {
  59         struct rb_node rb_node;
  60         ext4_lblk_t es_lblk;    /* first logical block extent covers */
  61         ext4_lblk_t es_len;     /* length of extent in block */
  62         ext4_fsblk_t es_pblk;   /* first physical block */
  63 };
  64
  65 struct ext4_es_tree {
  66         struct rb_root root;
  67         struct extent_status *cache_es; /* recently accessed extent */
  68 };
  69
  70 struct ext4_es_stats {
  71         unsigned long es_stats_shrunk;
  72         unsigned long es_stats_cache_hits;
  73         unsigned long es_stats_cache_misses;
  74         u64 es_stats_scan_time;
  75         u64 es_stats_max_scan_time;
  76         struct percpu_counter es_stats_all_cnt;
  77         struct percpu_counter es_stats_shk_cnt;
  78 };
  79
  80 extern int __init ext4_init_es(void);
  81 extern void ext4_exit_es(void);
  82 extern void ext4_es_init_tree(struct ext4_es_tree *tree);
  83
  84 extern int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
  85                                  ext4_lblk_t len, ext4_fsblk_t pblk,
  86                                  unsigned int status);
  87 extern void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk,
  88                                  ext4_lblk_t len, ext4_fsblk_t pblk,
  89                                  unsigned int status);
  90 extern int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
  91                                  ext4_lblk_t len);
  92 extern void ext4_es_find_delayed_extent_range(struct inode *inode,
  93                                         ext4_lblk_t lblk, ext4_lblk_t end,
  94                                         struct extent_status *es);
  95 extern int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
  96                                  struct extent_status *es);
  97
  98 static inline unsigned int ext4_es_status(struct extent_status *es)
  99 {
 100         return es->es_pblk >> ES_SHIFT;
 101 }
 102
 103 static inline unsigned int ext4_es_type(struct extent_status *es)
 104 {
 105         return (es->es_pblk & ES_TYPE_MASK) >> ES_SHIFT;
 106 }
 107
 108 static inline int ext4_es_is_written(struct extent_status *es)
 109 {
 110         return (ext4_es_type(es) & EXTENT_STATUS_WRITTEN) != 0;
 111 }
 112
 113 static inline int ext4_es_is_unwritten(struct extent_status *es)
 114 {
 115         return (ext4_es_type(es) & EXTENT_STATUS_UNWRITTEN) != 0;
 116 }
 117
 118 static inline int ext4_es_is_delayed(struct extent_status *es)
 119 {
 120         return (ext4_es_type(es) & EXTENT_STATUS_DELAYED) != 0;
 121 }
 122
 123 static inline int ext4_es_is_hole(struct extent_status *es)
 124 {
 125         return (ext4_es_type(es) & EXTENT_STATUS_HOLE) != 0;
 126 }
 127
 128 static inline void ext4_es_set_referenced(struct extent_status *es)
 129 {
 130         es->es_pblk |= ((ext4_fsblk_t)EXTENT_STATUS_REFERENCED) << ES_SHIFT;
 131 }
 132
 133 static inline void ext4_es_clear_referenced(struct extent_status *es)
 134 {
 135         es->es_pblk &= ~(((ext4_fsblk_t)EXTENT_STATUS_REFERENCED) << ES_SHIFT);
 136 }
 137
 138 static inline int ext4_es_is_referenced(struct extent_status *es)
 139 {
 140         return (ext4_es_status(es) & EXTENT_STATUS_REFERENCED) != 0;
 141 }
 142
 143 static inline ext4_fsblk_t ext4_es_pblock(struct extent_status *es)
 144 {
 145         return es->es_pblk & ~ES_MASK;
 146 }
 147
 148 static inline void ext4_es_store_pblock(struct extent_status *es,
 149                                         ext4_fsblk_t pb)
 150 {
 151         ext4_fsblk_t block;
 152
 153         block = (pb & ~ES_MASK) | (es->es_pblk & ES_MASK);
 154         es->es_pblk = block;
 155 }
 156
 157 static inline void ext4_es_store_status(struct extent_status *es,
 158                                         unsigned int status)
 159 {
 160         es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) |
 161                       (es->es_pblk & ~ES_MASK);
 162 }
 163
 164 static inline void ext4_es_store_pblock_status(struct extent_status *es,
 165                                                ext4_fsblk_t pb,
 166                                                unsigned int status)
 167 {
 168         es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) |
 169                       (pb & ~ES_MASK);
 170 }
 171
 172 extern int ext4_es_register_shrinker(struct ext4_sb_info *sbi);
 173 extern void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi);
 174
 175 #endif /* _EXT4_EXTENTS_STATUS_H */