FS-Cache: Allow the current state of all objects to be dumped
[linux-2.6.git] / fs / fscache / proc.c
1 /* FS-Cache statistics viewing interface
2  *
3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11
12 #define FSCACHE_DEBUG_LEVEL OPERATION
13 #include <linux/module.h>
14 #include <linux/proc_fs.h>
15 #include <linux/seq_file.h>
16 #include "internal.h"
17
18 /*
19  * initialise the /proc/fs/fscache/ directory
20  */
21 int __init fscache_proc_init(void)
22 {
23         _enter("");
24
25         if (!proc_mkdir("fs/fscache", NULL))
26                 goto error_dir;
27
28 #ifdef CONFIG_FSCACHE_STATS
29         if (!proc_create("fs/fscache/stats", S_IFREG | 0444, NULL,
30                          &fscache_stats_fops))
31                 goto error_stats;
32 #endif
33
34 #ifdef CONFIG_FSCACHE_HISTOGRAM
35         if (!proc_create("fs/fscache/histogram", S_IFREG | 0444, NULL,
36                          &fscache_histogram_fops))
37                 goto error_histogram;
38 #endif
39
40 #ifdef CONFIG_FSCACHE_OBJECT_LIST
41         if (!proc_create("fs/fscache/objects", S_IFREG | 0444, NULL,
42                          &fscache_objlist_fops))
43                 goto error_objects;
44 #endif
45
46         _leave(" = 0");
47         return 0;
48
49 #ifdef CONFIG_FSCACHE_OBJECT_LIST
50 error_objects:
51 #endif
52 #ifdef CONFIG_FSCACHE_HISTOGRAM
53         remove_proc_entry("fs/fscache/histogram", NULL);
54 error_histogram:
55 #endif
56 #ifdef CONFIG_FSCACHE_STATS
57         remove_proc_entry("fs/fscache/stats", NULL);
58 error_stats:
59 #endif
60         remove_proc_entry("fs/fscache", NULL);
61 error_dir:
62         _leave(" = -ENOMEM");
63         return -ENOMEM;
64 }
65
66 /*
67  * clean up the /proc/fs/fscache/ directory
68  */
69 void fscache_proc_cleanup(void)
70 {
71 #ifdef CONFIG_FSCACHE_OBJECT_LIST
72         remove_proc_entry("fs/fscache/objects", NULL);
73 #endif
74 #ifdef CONFIG_FSCACHE_HISTOGRAM
75         remove_proc_entry("fs/fscache/histogram", NULL);
76 #endif
77 #ifdef CONFIG_FSCACHE_STATS
78         remove_proc_entry("fs/fscache/stats", NULL);
79 #endif
80         remove_proc_entry("fs/fscache", NULL);
81 }