ocfs2: Document /sys/fs/ocfs2
Add ABI documentation for these files:
/sys/fs/ocfs2/max_locking_protocol
/sys/fs/ocfs2/loaded_cluster_plugins
/sys/fs/ocfs2/active_cluster_plugin
/sys/fs/ocfs2/cluster_stack
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
diff --git a/Documentation/ABI/testing/sysfs-ocfs2 b/Documentation/ABI/testing/sysfs-ocfs2
new file mode 100644
index 0000000..b7cc516
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+++ b/Documentation/ABI/testing/sysfs-ocfs2
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+What: /sys/fs/ocfs2/
+Date: April 2008
+Contact: ocfs2-devel@oss.oracle.com
+Description:
+ The /sys/fs/ocfs2 directory contains knobs used by the
+ ocfs2-tools to interact with the filesystem.
+
+What: /sys/fs/ocfs2/max_locking_protocol
+Date: April 2008
+Contact: ocfs2-devel@oss.oracle.com
+Description:
+ The /sys/fs/ocfs2/max_locking_protocol file displays version
+ of ocfs2 locking supported by the filesystem. This version
+ covers how ocfs2 uses distributed locking between cluster
+ nodes.
+
+ The protocol version has a major and minor number. Two
+ cluster nodes can interoperate if they have an identical
+ major number and an overlapping minor number - thus,
+ a node with version 1.10 can interoperate with a node
+ sporting version 1.8, as long as both use the 1.8 protocol.
+
+ Reading from this file returns a single line, the major
+ number and minor number joined by a period, eg "1.10".
+
+ This file is read-only. The value is compiled into the
+ driver.
+
+What: /sys/fs/ocfs2/loaded_cluster_plugins
+Date: April 2008
+Contact: ocfs2-devel@oss.oracle.com
+Description:
+ The /sys/fs/ocfs2/loaded_cluster_plugins file describes
+ the available plugins to support ocfs2 cluster operation.
+ A cluster plugin is required to use ocfs2 in a cluster.
+ There are currently two available plugins:
+
+ * 'o2cb' - The classic o2cb cluster stack that ocfs2 has
+ used since its inception.
+ * 'user' - A plugin supporting userspace cluster software
+ in conjunction with fs/dlm.
+
+ Reading from this file returns the names of all loaded
+ plugins, one per line.
+
+ This file is read-only. Its contents may change as
+ plugins are loaded or removed.
+
+What: /sys/fs/ocfs2/active_cluster_plugin
+Date: April 2008
+Contact: ocfs2-devel@oss.oracle.com
+Description:
+ The /sys/fs/ocfs2/active_cluster_plugin displays which
+ cluster plugin is currently in use by the filesystem.
+ The active plugin will appear in the loaded_cluster_plugins
+ file as well. Only one plugin can be used at a time.
+
+ Reading from this file returns the name of the active plugin
+ on a single line.
+
+ This file is read-only. Which plugin is active depends on
+ the cluster stack in use. The contents may change
+ when all filesystems are unmounted and the cluster stack
+ is changed.
+
+What: /sys/fs/ocfs2/cluster_stack
+Date: April 2008
+Contact: ocfs2-devel@oss.oracle.com
+Description:
+ The /sys/fs/ocfs2/cluster_stack file contains the name
+ of current ocfs2 cluster stack. This value is set by
+ userspace tools when bringing the cluster stack online.
+
+ Cluster stack names are 4 characters in length.
+
+ When the 'o2cb' cluster stack is used, the 'o2cb' cluster
+ plugin is active. All other cluster stacks use the 'user'
+ cluster plugin.
+
+ Reading from this file returns the name of the current
+ cluster stack on a single line.
+
+ Writing a new stack name to this file changes the current
+ cluster stack unless there are mounted ocfs2 filesystems.
+ If there are mounted filesystems, attempts to change the
+ stack return an error.
+
+Users:
+ ocfs2-tools <ocfs2-tools-devel@oss.oracle.com>