xref: /linux/fs/ext4/extents_status.h (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
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 struct extent_status {
24 	struct rb_node rb_node;
25 	ext4_lblk_t start;	/* first block extent covers */
26 	ext4_lblk_t len;	/* length of extent in block */
27 };
28 
29 struct ext4_es_tree {
30 	struct rb_root root;
31 	struct extent_status *cache_es;	/* recently accessed extent */
32 };
33 
34 extern int __init ext4_init_es(void);
35 extern void ext4_exit_es(void);
36 extern void ext4_es_init_tree(struct ext4_es_tree *tree);
37 
38 extern int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t start,
39 				 ext4_lblk_t len);
40 extern int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t start,
41 				 ext4_lblk_t len);
42 extern ext4_lblk_t ext4_es_find_extent(struct inode *inode,
43 				struct extent_status *es);
44 
45 #endif /* _EXT4_EXTENTS_STATUS_H */
46