Commit 5b7ac27a authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab Committed by Jonathan Corbet
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docs: filesystems: convert gfs2-uevents.txt to ReST 



This document is almost in ReST format: all it needs is to have
the titles adjusted and add a SPDX header. In other words:

- Add a SPDX header;
- Add a document title;
- Adjust section titles;
- Add it to filesystems/index.rst.

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: default avatarBob Peterson <rpeterso@redhat.com>
Link: https://lore.kernel.org/r/1d1c46b7e86bd0a18d9abbea0de0bc2be84e5e2b.1581955849.git.mchehab+huawei@kernel.org


Signed-off-by: default avatarJonathan Corbet <corbet@lwn.net>
parent 720c2fc1

Documentation/filesystems/gfs2-uevents.txt→Documentation/filesystems/gfs2-uevents.rst

+16 −4
Original line number Diff line number Diff line 
.. SPDX-License-Identifier: GPL-2.0



================

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).



A list of GFS2 uevents

-----------------------

======================



1. ADD

------



The ADD event occurs at mount time. It will always be the first

uevent generated by the newly created filesystem. If the mount
@@ -21,6 +25,7 @@ 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
@@ -29,6 +34,7 @@ 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

successful mount of the filesystem by the first node (FIRSTMOUNT=Done).
@@ -52,6 +58,7 @@ cluster. For this reason the ONLINE uevent was used when adding a new 
uevent for a successful mount or remount.



4. OFFLINE

----------



The OFFLINE uevent is only generated due to filesystem errors and is used

as part of the "withdraw" mechanism. Currently this doesn't give any
@@ -59,6 +66,7 @@ information about what the error is, which is something that needs to 
be fixed.



5. REMOVE

---------



The REMOVE uevent is generated at the end of an unsuccessful mount

or at the end of a umount of the filesystem. All REMOVE uevents will
@@ -68,9 +76,10 @@ kobject subsystem. 




Information common to all GFS2 uevents (uevent environment variables)

----------------------------------------------------------------------

=====================================================================



1. LOCKTABLE=

--------------



The LOCKTABLE is a string, as supplied on the mount command

line (locktable=) or via fstab. It is used as a filesystem label
@@ -78,6 +87,7 @@ as well as providing the information for a lock_dlm mount to be 
able to join the cluster.



2. LOCKPROTO=

-------------



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
@@ -85,12 +95,14 @@ lock_nolock or lock_dlm. In the future other lock managers 
may be supported.



3. JOURNALID=

-------------



If a journal is in use by the filesystem (journals are not

assigned for spectator mounts) then this will give the

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, this will

Documentation/filesystems/index.rst

+1 −0
Original line number Diff line number Diff line
@@ -66,6 +66,7 @@ Documentation for filesystem implementations. 
   ext3

   f2fs

   gfs2

   gfs2-uevents

   fuse

   overlayfs

   virtiofs

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