xref: /linux/Documentation/ABI/testing/sysfs-ocfs2 (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1What:		/sys/fs/ocfs2/
2Date:		April 2008
3Contact:	ocfs2-devel@lists.linux.dev
4Description:
5		The /sys/fs/ocfs2 directory contains knobs used by the
6		ocfs2-tools to interact with the filesystem.
7
8What:		/sys/fs/ocfs2/max_locking_protocol
9Date:		April 2008
10Contact:	ocfs2-devel@lists.linux.dev
11Description:
12		The /sys/fs/ocfs2/max_locking_protocol file displays version
13		of ocfs2 locking supported by the filesystem.  This version
14		covers how ocfs2 uses distributed locking between cluster
15		nodes.
16
17		The protocol version has a major and minor number.  Two
18		cluster nodes can interoperate if they have an identical
19		major number and an overlapping minor number - thus,
20		a node with version 1.10 can interoperate with a node
21		sporting version 1.8, as long as both use the 1.8 protocol.
22
23		Reading from this file returns a single line, the major
24		number and minor number joined by a period, eg "1.10".
25
26		This file is read-only.  The value is compiled into the
27		driver.
28
29What:		/sys/fs/ocfs2/loaded_cluster_plugins
30Date:		April 2008
31Contact:	ocfs2-devel@lists.linux.dev
32Description:
33		The /sys/fs/ocfs2/loaded_cluster_plugins file describes
34		the available plugins to support ocfs2 cluster operation.
35		A cluster plugin is required to use ocfs2 in a cluster.
36		There are currently two available plugins:
37
38		* 'o2cb' - The classic o2cb cluster stack that ocfs2 has
39			used since its inception.
40		* 'user' - A plugin supporting userspace cluster software
41			in conjunction with fs/dlm.
42
43		Reading from this file returns the names of all loaded
44		plugins, one per line.
45
46		This file is read-only.  Its contents may change as
47		plugins are loaded or removed.
48
49What:		/sys/fs/ocfs2/active_cluster_plugin
50Date:		April 2008
51Contact:	ocfs2-devel@lists.linux.dev
52Description:
53		The /sys/fs/ocfs2/active_cluster_plugin displays which
54		cluster plugin is currently in use by the filesystem.
55		The active plugin will appear in the loaded_cluster_plugins
56		file as well.  Only one plugin can be used at a time.
57
58		Reading from this file returns the name of the active plugin
59		on a single line.
60
61		This file is read-only.  Which plugin is active depends on
62		the cluster stack in use.  The contents may change
63		when all filesystems are unmounted and the cluster stack
64		is changed.
65
66What:		/sys/fs/ocfs2/cluster_stack
67Date:		April 2008
68Contact:	ocfs2-devel@lists.linux.dev
69Description:
70		The /sys/fs/ocfs2/cluster_stack file contains the name
71		of current ocfs2 cluster stack.  This value is set by
72		userspace tools when bringing the cluster stack online.
73
74		Cluster stack names are 4 characters in length.
75
76		When the 'o2cb' cluster stack is used, the 'o2cb' cluster
77		plugin is active.  All other cluster stacks use the 'user'
78		cluster plugin.
79
80		Reading from this file returns the name of the current
81		cluster stack on a single line.
82
83		Writing a new stack name to this file changes the current
84		cluster stack unless there are mounted ocfs2 filesystems.
85		If there are mounted filesystems, attempts to change the
86		stack return an error.
87
88Users:
89	ocfs2-tools <ocfs2-tools-devel@lists.linux.dev>
90