LXR linux/fs/ext4/extents

   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 */
  32enum {
  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
  55struct ext4_sb_info;
  56struct ext4_extent;
  57
  58struct 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
  65struct ext4_es_tree {
  66        struct rb_root root;
  67        struct extent_status *cache_es; /* recently accessed extent */
  68};
  69
  70struct 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
  80extern int __init ext4_init_es(void);
  81extern void ext4_exit_es(void);
  82extern void ext4_es_init_tree(struct ext4_es_tree *tree);
  83
  84extern 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);
  87extern 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);
  90extern int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
  91                                 ext4_lblk_t len);
  92extern void ext4_es_find_delayed_extent_range(struct inode *inode,
  93                                        ext4_lblk_t lblk, ext4_lblk_t end,
  94                                        struct extent_status *es);
  95extern int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
  96                                 struct extent_status *es);
  97
  98static inline unsigned int ext4_es_status(struct extent_status *es)
  99{
 100        return es->es_pblk >> ES_SHIFT;
 101}
 102
 103static inline unsigned int ext4_es_type(struct extent_status *es)
 104{
 105        return (es->es_pblk & ES_TYPE_MASK) >> ES_SHIFT;
 106}
 107
 108static inline int ext4_es_is_written(struct extent_status *es)
 109{
 110        return (ext4_es_type(es) & EXTENT_STATUS_WRITTEN) != 0;
 111}
 112
 113static inline int ext4_es_is_unwritten(struct extent_status *es)
 114{
 115        return (ext4_es_type(es) & EXTENT_STATUS_UNWRITTEN) != 0;
 116}
 117
 118static inline int ext4_es_is_delayed(struct extent_status *es)
 119{
 120        return (ext4_es_type(es) & EXTENT_STATUS_DELAYED) != 0;
 121}
 122
 123static inline int ext4_es_is_hole(struct extent_status *es)
 124{
 125        return (ext4_es_type(es) & EXTENT_STATUS_HOLE) != 0;
 126}
 127
 128static 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
 133static 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
 138static inline int ext4_es_is_referenced(struct extent_status *es)
 139{
 140        return (ext4_es_status(es) & EXTENT_STATUS_REFERENCED) != 0;
 141}
 142
 143static inline ext4_fsblk_t ext4_es_pblock(struct extent_status *es)
 144{
 145        return es->es_pblk & ~ES_MASK;
 146}
 147
 148static 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
 157static 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
 164static 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
 172extern int ext4_es_register_shrinker(struct ext4_sb_info *sbi);
 173extern void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi);
 174
 175extern int ext4_seq_es_shrinker_info_show(struct seq_file *seq, void *v);
 176
 177#endif /* _EXT4_EXTENTS_STATUS_H */
 178