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 #define ES_SHIFT        60
  33
  34 #define EXTENT_STATUS_WRITTEN   (1 << 3)
  35 #define EXTENT_STATUS_UNWRITTEN (1 << 2)
  36 #define EXTENT_STATUS_DELAYED   (1 << 1)
  37 #define EXTENT_STATUS_HOLE      (1 << 0)
  38
  39 #define EXTENT_STATUS_FLAGS     (EXTENT_STATUS_WRITTEN | \
  40                                  EXTENT_STATUS_UNWRITTEN | \
  41                                  EXTENT_STATUS_DELAYED | \
  42                                  EXTENT_STATUS_HOLE)
  43
  44 #define ES_WRITTEN              (1ULL << 63)
  45 #define ES_UNWRITTEN            (1ULL << 62)
  46 #define ES_DELAYED              (1ULL << 61)
  47 #define ES_HOLE                 (1ULL << 60)
  48
  49 #define ES_MASK                 (ES_WRITTEN | ES_UNWRITTEN | \
  50                                  ES_DELAYED | ES_HOLE)
  51
  52 struct ext4_sb_info;
  53 struct ext4_extent;
  54
  55 struct extent_status {
  56         struct rb_node rb_node;
  57         ext4_lblk_t es_lblk;    /* first logical block extent covers */
  58         ext4_lblk_t es_len;     /* length of extent in block */
  59         ext4_fsblk_t es_pblk;   /* first physical block */
  60 };
  61
  62 struct ext4_es_tree {
  63         struct rb_root root;
  64         struct extent_status *cache_es; /* recently accessed extent */
  65 };
  66
  67 extern int __init ext4_init_es(void);
  68 extern void ext4_exit_es(void);
  69 extern void ext4_es_init_tree(struct ext4_es_tree *tree);
  70
  71 extern int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
  72                                  ext4_lblk_t len, ext4_fsblk_t pblk,
  73                                  unsigned int status);
  74 extern void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk,
  75                                  ext4_lblk_t len, ext4_fsblk_t pblk,
  76                                  unsigned int status);
  77 extern int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
  78                                  ext4_lblk_t len);
  79 extern void ext4_es_find_delayed_extent_range(struct inode *inode,
  80                                         ext4_lblk_t lblk, ext4_lblk_t end,
  81                                         struct extent_status *es);
  82 extern int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
  83                                  struct extent_status *es);
  84
  85 static inline int ext4_es_is_written(struct extent_status *es)
  86 {
  87         return (es->es_pblk & ES_WRITTEN) != 0;
  88 }
  89
  90 static inline int ext4_es_is_unwritten(struct extent_status *es)
  91 {
  92         return (es->es_pblk & ES_UNWRITTEN) != 0;
  93 }
  94
  95 static inline int ext4_es_is_delayed(struct extent_status *es)
  96 {
  97         return (es->es_pblk & ES_DELAYED) != 0;
  98 }
  99
 100 static inline int ext4_es_is_hole(struct extent_status *es)
 101 {
 102         return (es->es_pblk & ES_HOLE) != 0;
 103 }
 104
 105 static inline unsigned int ext4_es_status(struct extent_status *es)
 106 {
 107         return es->es_pblk >> ES_SHIFT;
 108 }
 109
 110 static inline ext4_fsblk_t ext4_es_pblock(struct extent_status *es)
 111 {
 112         return es->es_pblk & ~ES_MASK;
 113 }
 114
 115 static inline void ext4_es_store_pblock(struct extent_status *es,
 116                                         ext4_fsblk_t pb)
 117 {
 118         ext4_fsblk_t block;
 119
 120         block = (pb & ~ES_MASK) | (es->es_pblk & ES_MASK);
 121         es->es_pblk = block;
 122 }
 123
 124 static inline void ext4_es_store_status(struct extent_status *es,
 125                                         unsigned int status)
 126 {
 127         es->es_pblk = (((ext4_fsblk_t)
 128                         (status & EXTENT_STATUS_FLAGS) << ES_SHIFT) |
 129                        (es->es_pblk & ~ES_MASK));
 130 }
 131
 132 extern void ext4_es_register_shrinker(struct ext4_sb_info *sbi);
 133 extern void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi);
 134 extern void ext4_es_lru_add(struct inode *inode);
 135 extern void ext4_es_lru_del(struct inode *inode);
 136
 137 #endif /* _EXT4_EXTENTS_STATUS_H */