linux/fs/ext4/extents_status.h
Jan Kara 624d0f1dd7 ext4: cleanup flag definitions for extent status tree
Currently flags for extent status tree are defined twice, once shifted
and once without a being shifted. Consolidate these definitions into one
place and make some computations automatic to make adding flags less
error prone. Compiler should be clever enough to figure out these are
constants and generate the same code.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-11-25 11:53:47 -05:00

149 lines
3.9 KiB
C

/*
* fs/ext4/extents_status.h
*
* Written by Yongqiang Yang <xiaoqiangnk@gmail.com>
* Modified by
* Allison Henderson <achender@linux.vnet.ibm.com>
* Zheng Liu <wenqing.lz@taobao.com>
*
*/
#ifndef _EXT4_EXTENTS_STATUS_H
#define _EXT4_EXTENTS_STATUS_H
/*
* Turn on ES_DEBUG__ to get lots of info about extent status operations.
*/
#ifdef ES_DEBUG__
#define es_debug(fmt, ...) printk(fmt, ##__VA_ARGS__)
#else
#define es_debug(fmt, ...) no_printk(fmt, ##__VA_ARGS__)
#endif
/*
* With ES_AGGRESSIVE_TEST defined, the result of es caching will be
* checked with old map_block's result.
*/
#define ES_AGGRESSIVE_TEST__
/*
* These flags live in the high bits of extent_status.es_pblk
*/
enum {
ES_WRITTEN_B,
ES_UNWRITTEN_B,
ES_DELAYED_B,
ES_HOLE_B,
ES_FLAGS
};
#define ES_SHIFT (sizeof(ext4_fsblk_t)*8 - ES_FLAGS)
#define ES_MASK (~((ext4_fsblk_t)0) << ES_SHIFT)
#define EXTENT_STATUS_WRITTEN (1 << ES_WRITTEN_B)
#define EXTENT_STATUS_UNWRITTEN (1 << ES_UNWRITTEN_B)
#define EXTENT_STATUS_DELAYED (1 << ES_DELAYED_B)
#define EXTENT_STATUS_HOLE (1 << ES_HOLE_B)
struct ext4_sb_info;
struct ext4_extent;
struct extent_status {
struct rb_node rb_node;
ext4_lblk_t es_lblk; /* first logical block extent covers */
ext4_lblk_t es_len; /* length of extent in block */
ext4_fsblk_t es_pblk; /* first physical block */
};
struct ext4_es_tree {
struct rb_root root;
struct extent_status *cache_es; /* recently accessed extent */
};
struct ext4_es_stats {
unsigned long es_stats_shrunk;
unsigned long es_stats_cache_hits;
unsigned long es_stats_cache_misses;
u64 es_stats_scan_time;
u64 es_stats_max_scan_time;
struct percpu_counter es_stats_all_cnt;
struct percpu_counter es_stats_shk_cnt;
};
extern int __init ext4_init_es(void);
extern void ext4_exit_es(void);
extern void ext4_es_init_tree(struct ext4_es_tree *tree);
extern int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
ext4_lblk_t len, ext4_fsblk_t pblk,
unsigned int status);
extern void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk,
ext4_lblk_t len, ext4_fsblk_t pblk,
unsigned int status);
extern int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
ext4_lblk_t len);
extern void ext4_es_find_delayed_extent_range(struct inode *inode,
ext4_lblk_t lblk, ext4_lblk_t end,
struct extent_status *es);
extern int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
struct extent_status *es);
static inline unsigned int ext4_es_status(struct extent_status *es)
{
return es->es_pblk >> ES_SHIFT;
}
static inline int ext4_es_is_written(struct extent_status *es)
{
return (ext4_es_status(es) & EXTENT_STATUS_WRITTEN) != 0;
}
static inline int ext4_es_is_unwritten(struct extent_status *es)
{
return (ext4_es_status(es) & EXTENT_STATUS_UNWRITTEN) != 0;
}
static inline int ext4_es_is_delayed(struct extent_status *es)
{
return (ext4_es_status(es) & EXTENT_STATUS_DELAYED) != 0;
}
static inline int ext4_es_is_hole(struct extent_status *es)
{
return (ext4_es_status(es) & EXTENT_STATUS_HOLE) != 0;
}
static inline ext4_fsblk_t ext4_es_pblock(struct extent_status *es)
{
return es->es_pblk & ~ES_MASK;
}
static inline void ext4_es_store_pblock(struct extent_status *es,
ext4_fsblk_t pb)
{
ext4_fsblk_t block;
block = (pb & ~ES_MASK) | (es->es_pblk & ES_MASK);
es->es_pblk = block;
}
static inline void ext4_es_store_status(struct extent_status *es,
unsigned int status)
{
es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) |
(es->es_pblk & ~ES_MASK);
}
static inline void ext4_es_store_pblock_status(struct extent_status *es,
ext4_fsblk_t pb,
unsigned int status)
{
es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) |
(pb & ~ES_MASK);
}
extern int ext4_es_register_shrinker(struct ext4_sb_info *sbi);
extern void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi);
#endif /* _EXT4_EXTENTS_STATUS_H */