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
 52struct ext4_sb_info;
 53struct ext4_extent;
 54
 55struct 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
 62struct ext4_es_tree {
 63	struct rb_root root;
 64	struct extent_status *cache_es;	/* recently accessed extent */
 65};
 66
 67extern int __init ext4_init_es(void);
 68extern void ext4_exit_es(void);
 69extern void ext4_es_init_tree(struct ext4_es_tree *tree);
 70
 71extern 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);
 74extern 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);
 77extern int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
 78				 ext4_lblk_t len);
 79extern void ext4_es_find_delayed_extent_range(struct inode *inode,
 80					ext4_lblk_t lblk, ext4_lblk_t end,
 81					struct extent_status *es);
 82extern int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
 83				 struct extent_status *es);
 84
 85static inline int ext4_es_is_written(struct extent_status *es)
 86{
 87	return (es->es_pblk & ES_WRITTEN) != 0;
 88}
 89
 90static inline int ext4_es_is_unwritten(struct extent_status *es)
 91{
 92	return (es->es_pblk & ES_UNWRITTEN) != 0;
 93}
 94
 95static inline int ext4_es_is_delayed(struct extent_status *es)
 96{
 97	return (es->es_pblk & ES_DELAYED) != 0;
 98}
 99
100static inline int ext4_es_is_hole(struct extent_status *es)
101{
102	return (es->es_pblk & ES_HOLE) != 0;
103}
104
105static inline unsigned int ext4_es_status(struct extent_status *es)
106{
107	return es->es_pblk >> ES_SHIFT;
108}
109
110static inline ext4_fsblk_t ext4_es_pblock(struct extent_status *es)
111{
112	return es->es_pblk & ~ES_MASK;
113}
114
115static 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
124static 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
132static inline void ext4_es_store_pblock_status(struct extent_status *es,
133					       ext4_fsblk_t pb,
134					       unsigned int status)
135{
136	es->es_pblk = (((ext4_fsblk_t)
137			(status & EXTENT_STATUS_FLAGS) << ES_SHIFT) |
138		       (pb & ~ES_MASK));
139}
140
141extern void ext4_es_register_shrinker(struct ext4_sb_info *sbi);
142extern void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi);
143extern void ext4_es_lru_add(struct inode *inode);
144extern void ext4_es_lru_del(struct inode *inode);
145
146#endif /* _EXT4_EXTENTS_STATUS_H */