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 */