xref: /openbmc/linux/fs/nilfs2/sufile.h (revision b04b4f78)
1 /*
2  * sufile.h - NILFS segment usage file.
3  *
4  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
19  *
20  * Written by Koji Sato <koji@osrg.net>.
21  */
22 
23 #ifndef _NILFS_SUFILE_H
24 #define _NILFS_SUFILE_H
25 
26 #include <linux/fs.h>
27 #include <linux/buffer_head.h>
28 #include <linux/nilfs2_fs.h>
29 #include "mdt.h"
30 
31 #define NILFS_SUFILE_GFP	NILFS_MDT_GFP
32 
33 static inline unsigned long nilfs_sufile_get_nsegments(struct inode *sufile)
34 {
35 	return NILFS_MDT(sufile)->mi_nilfs->ns_nsegments;
36 }
37 
38 int nilfs_sufile_alloc(struct inode *, __u64 *);
39 int nilfs_sufile_get_segment_usage(struct inode *, __u64,
40 				   struct nilfs_segment_usage **,
41 				   struct buffer_head **);
42 void nilfs_sufile_put_segment_usage(struct inode *, __u64,
43 				    struct buffer_head *);
44 int nilfs_sufile_get_stat(struct inode *, struct nilfs_sustat *);
45 int nilfs_sufile_get_ncleansegs(struct inode *, unsigned long *);
46 ssize_t nilfs_sufile_get_suinfo(struct inode *, __u64, struct nilfs_suinfo *,
47 				size_t);
48 
49 int nilfs_sufile_update(struct inode *, __u64, int,
50 			void (*dofunc)(struct inode *, __u64,
51 				       struct buffer_head *,
52 				       struct buffer_head *));
53 void nilfs_sufile_do_cancel_free(struct inode *, __u64, struct buffer_head *,
54 				 struct buffer_head *);
55 void nilfs_sufile_do_scrap(struct inode *, __u64, struct buffer_head *,
56 			   struct buffer_head *);
57 void nilfs_sufile_do_free(struct inode *, __u64, struct buffer_head *,
58 			  struct buffer_head *);
59 void nilfs_sufile_do_set_error(struct inode *, __u64, struct buffer_head *,
60 			       struct buffer_head *);
61 
62 /**
63  * nilfs_sufile_cancel_free -
64  * @sufile: inode of segment usage file
65  * @segnum: segment number
66  *
67  * Description:
68  *
69  * Return Value: On success, 0 is returned. On error, one of the following
70  * negative error codes is returned.
71  *
72  * %-EIO - I/O error.
73  *
74  * %-ENOMEM - Insufficient amount of memory available.
75  */
76 static inline int nilfs_sufile_cancel_free(struct inode *sufile, __u64 segnum)
77 {
78 	return nilfs_sufile_update(sufile, segnum, 0,
79 				   nilfs_sufile_do_cancel_free);
80 }
81 
82 /**
83  * nilfs_sufile_scrap - make a segment garbage
84  * @sufile: inode of segment usage file
85  * @segnum: segment number to be freed
86  */
87 static inline int nilfs_sufile_scrap(struct inode *sufile, __u64 segnum)
88 {
89 	return nilfs_sufile_update(sufile, segnum, 1, nilfs_sufile_do_scrap);
90 }
91 
92 /**
93  * nilfs_sufile_free - free segment
94  * @sufile: inode of segment usage file
95  * @segnum: segment number to be freed
96  */
97 static inline int nilfs_sufile_free(struct inode *sufile, __u64 segnum)
98 {
99 	return nilfs_sufile_update(sufile, segnum, 0, nilfs_sufile_do_free);
100 }
101 
102 /**
103  * nilfs_sufile_set_error - mark a segment as erroneous
104  * @sufile: inode of segment usage file
105  * @segnum: segment number
106  *
107  * Description: nilfs_sufile_set_error() marks the segment specified by
108  * @segnum as erroneous. The error segment will never be used again.
109  *
110  * Return Value: On success, 0 is returned. On error, one of the following
111  * negative error codes is returned.
112  *
113  * %-EIO - I/O error.
114  *
115  * %-ENOMEM - Insufficient amount of memory available.
116  *
117  * %-EINVAL - Invalid segment usage number.
118  */
119 static inline int nilfs_sufile_set_error(struct inode *sufile, __u64 segnum)
120 {
121 	return nilfs_sufile_update(sufile, segnum, 0,
122 				   nilfs_sufile_do_set_error);
123 }
124 
125 #endif	/* _NILFS_SUFILE_H */
126