[Cluster-devel] GFS2 and uevents document

[Bob Peterson]

----- "Steven Whitehouse" <swhiteho at redhat.com> wrote:
| Hi,
| 
| Below is a first draft at a document explaining the uevents produced
| by
| GFS2. I'm intending to add it under
| linux-2.6/Documentation/filesystems/gfs-uevents.txt
| 
| Let me know if you spot anything thats wrong or could be better
| explained,
| 
| Steve.

Hi Steve,

Good writeup.  Here are some minor suggestions.

Bob Peterson
--
--- /home/msp/rpeterso/gfs_uevents.orig.txt	2009-08-13 10:02:25.000000000 -0500
+++ /home/msp/rpeterso/gfs_uevents.bobs.txt	2009-08-13 10:10:33.000000000 -0500
@@ -1,9 +1,9 @@
                               uevents and GFS2
                              ==================
 
-During the lifetime of a GFS2 mount, a number of uevents are generated,
-this document explains what the events are and what they are used
-for (by gfs_controld in gfs2-utils)
+During the lifetime of a GFS2 mount, a number of uevents are generated.
+This document explains what the events are and what they are used
+for (by gfs_controld in gfs2-utils).
 
 A list of GFS2 uevents
 -----------------------
@@ -12,26 +12,26 @@ A list of GFS2 uevents
 
 The ADD event occurs at mount time. It will always be the first
 uevent generated by the newly created filesystem. If the mount
-is successful, an ONLINE uevent will follow, if it is not successful
+is successful, an ONLINE uevent will follow.  If it is not successful
 then a REMOVE uevent will follow.
 
 The ADD uevent has two environment variables: SPECTATOR=[0|1]
-and RDONLY=[0|1] which specify the spectator (no journal assigned,
-implies a read-only mount) and read-only status of the filesystem
-respectively.
+and RDONLY=[0|1] that specify the spectator status (a read-only mount
+with no journal assigned), and read-only (with journal assigned) status
+of the filesystem respectively.
 
 2. ONLINE
 
 The ONLINE uevent is generated after a successful mount or remount. It
 has the same environment variables as the ADD uevent. The ONLINE
 uevent, along with the two environment variables for spectator and
-rdonly are a relatively recent addition (2.6.32-rc+) and will not
+RDONLY are a relatively recent addition (2.6.32-rc+) and will not
 be generated by older kernels.
 
 3. CHANGE
 
 The CHANGE uevent is used in two places. One is when reporting the
-sucessful mount of the filesystem by the first node (FIRSTMOUNT=Done).
+successful mount of the filesystem by the first node (FIRSTMOUNT=Done).
 This is used as a signal by gfs_controld that it is then ok for other
 nodes in the cluster to mount the filesystem.
 
@@ -40,7 +40,7 @@ of journal recovery for one of the files
 two environment variables, JID= which specifies the journal id which
 has just been recovered, and RECOVERY=[Done|Failed] to indicate the
 success (or otherwise) of the operation. These uevents are generated
-for every journal recovered whether it is during the initial mount
+for every journal recovered, whether it is during the initial mount
 process or as the result of gfs_controld requesting a specific journal
 recovery via the /sys/fs/gfs2/<fsname>/lock_module/recovery file.
 
@@ -79,7 +79,7 @@ able to join the cluster.
 
 2. LOCKPROTO=
 
-The LOCKPROTO is a string, again its value depends on that set
+The LOCKPROTO is a string, and its value depends on what is set
 on the mount command line, or via fstab. It will be either
 lock_nolock or lock_dlm. In the future other lock managers
 may be supported.
@@ -93,7 +93,7 @@ numeric journal id in all GFS2 uevents.
 4. UUID=
 
 With recent versions of gfs2-utils, mkfs.gfs2 writes a UUID
-into the filesystem superblock. If it exists, then this will
+into the filesystem superblock. If it exists, this will
 be included in every uevent relating to the filesystem.