GFS2 Filesystem [13/16]

[Steven Whitehouse <swhiteho@redhat.com>]

[PATCH 13/16] GFS2: 

This hooks GFS2 into the kernel's build system. It also adds some
documentation. Note that the dlm has been moved to be under
fs/dlm as per Ingo Molnar's suggestion. This patch series doesn't
include the dlm however as its already in both -mm and the git
tree containing GFS2 at kernel.org.


Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>


 Documentation/filesystems/gfs2.txt |   44 +++++++++++++++++++++++++++++++++++
 fs/Kconfig                         |    6 ++--
 fs/Makefile                        |    2 +
 fs/gfs2/Kconfig                    |   46 +++++++++++++++++++++++++++++++++++++
 fs/gfs2/Makefile                   |   42 +++++++++++++++++++++++++++++++++
 5 files changed, 137 insertions(+), 3 deletions(-)

--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -323,6 +323,7 @@ config FS_POSIX_ACL
 	default n
 
 source "fs/xfs/Kconfig"
+source "fs/gfs2/Kconfig"
 
 config OCFS2_FS
 	tristate "OCFS2 file system support (EXPERIMENTAL)"
@@ -883,8 +884,6 @@ config CONFIGFS_FS
 	  Both sysfs and configfs can and should exist together on the
 	  same system. One is not a replacement for the other.
 
-	  If unsure, say N.
-
 endmenu
 
 menu "Miscellaneous filesystems"
@@ -1327,7 +1326,7 @@ config UFS_FS
 
 config UFS_FS_WRITE
 	bool "UFS file system write support (DANGEROUS)"
-	depends on UFS_FS && EXPERIMENTAL
+	depends on UFS_FS && EXPERIMENTAL && BROKEN
 	help
 	  Say Y here if you want to try writing to UFS partitions. This is
 	  experimental, so you should back up your UFS partitions beforehand.
@@ -1830,6 +1829,7 @@ source "fs/partitions/Kconfig"
 endmenu
 
 source "fs/nls/Kconfig"
+source "fs/dlm/Kconfig"
 
 endmenu
 
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -48,6 +48,7 @@ obj-$(CONFIG_SYSFS)		+= sysfs/
 obj-y				+= devpts/
 
 obj-$(CONFIG_PROFILING)		+= dcookies.o
+obj-$(CONFIG_DLM)		+= dlm/
  
 # Do not add any filesystems before this line
 obj-$(CONFIG_REISERFS_FS)	+= reiserfs/
@@ -103,3 +104,4 @@ obj-$(CONFIG_HPPFS)		+= hppfs/
 obj-$(CONFIG_DEBUG_FS)		+= debugfs/
 obj-$(CONFIG_CONFIGFS_FS)	+= configfs/
 obj-$(CONFIG_OCFS2_FS)		+= ocfs2/
+obj-$(CONFIG_GFS2_FS)           += gfs2/
--- /dev/null
+++ b/fs/gfs2/Makefile
@@ -0,0 +1,42 @@
+obj-$(CONFIG_GFS2_FS) += gfs2.o
+gfs2-y := \
+	acl.o \
+	bits.o \
+	bmap.o \
+	daemon.o \
+	dir.o \
+	eaops.o \
+	eattr.o \
+	glock.o \
+	glops.o \
+	inode.o \
+	lm.o \
+	log.o \
+	lops.o \
+	locking.o \
+	lvb.o \
+	main.o \
+	meta_io.o \
+	mount.o \
+	ondisk.o \
+	ops_address.o \
+	ops_dentry.o \
+	ops_export.o \
+	ops_file.o \
+	ops_fstype.o \
+	ops_inode.o \
+	ops_super.o \
+	ops_vm.o \
+	page.o \
+	quota.o \
+	recovery.o \
+	rgrp.o \
+	super.o \
+	sys.o \
+	trans.o \
+	unlinked.o \
+	util.o
+
+obj-$(CONFIG_GFS2_FS_LOCKING_NOLOCK) += locking/nolock/
+obj-$(CONFIG_GFS2_FS_LOCKING_DLM) += locking/dlm/
+
--- /dev/null
+++ b/fs/gfs2/Kconfig
@@ -0,0 +1,46 @@
+config GFS2_FS
+        tristate "GFS2 file system support"
+	default m
+	depends on EXPERIMENTAL
+        select FS_POSIX_ACL
+        select SYSFS
+        help
+        A cluster filesystem.
+
+        Allows a cluster of computers to simultaneously use a block device
+        that is shared between them (with FC, iSCSI, NBD, etc...).  GFS reads
+        and writes to the block device like a local filesystem, but also uses
+        a lock module to allow the computers coordinate their I/O so
+        filesystem consistency is maintained.  One of the nifty features of
+        GFS is perfect consistency -- changes made to the filesystem on one
+        machine show up immediately on all other machines in the cluster.
+
+	To use the GFS2 filesystem, you will need to enable one or more of
+	the below locking modules. Documentation and utilities for GFS2 can
+	be found here: http://sources.redhat.com/cluster/gfs/
+
+config GFS2_FS_LOCKING_NOLOCK
+	tristate "GFS2 \"nolock\" locking module"
+	depends on GFS2_FS
+	help
+	Single node locking module for GFS2.
+
+	Use this module if you want to use GFS2 on a single node without
+	its clustering features. You can still take advantage of the
+	large file support, and upgrade to running a full cluster later on
+	if required.
+
+	If you will only be using GFS2 in cluster mode, you do not need this
+	module.
+
+config GFS2_FS_LOCKING_DLM
+	tristate "GFS2 DLM locking module"
+	depends on GFS2_FS
+	select DLM
+	help
+	Multiple node locking module for GFS2
+
+	Most users of GFS2 will require this module. It provides the locking
+	interface between GFS2 and the DLM, which is required to use GFS2
+	in a cluster environment.
+
--- /dev/null
+++ b/Documentation/filesystems/gfs2.txt
@@ -0,0 +1,44 @@
+Global File System
+------------------
+
+http://sources.redhat.com/cluster/
+
+GFS is a cluster file system. It allows a cluster of computers to
+simultaneously use a block device that is shared between them (with FC,
+iSCSI, NBD, etc).  GFS reads and writes to the block device like a local
+file system, but also uses a lock module to allow the computers coordinate
+their I/O so file system consistency is maintained.  One of the nifty
+features of GFS is perfect consistency -- changes made to the file system
+on one machine show up immediately on all other machines in the cluster.
+
+GFS uses interchangable inter-node locking mechanisms.  Different lock
+modules can plug into GFS and each file system selects the appropriate
+lock module at mount time.  Lock modules include:
+
+  lock_nolock -- allows gfs to be used as a local file system
+
+  lock_dlm -- uses a distributed lock manager (dlm) for inter-node locking
+  The dlm is found at linux/fs/dlm/
+
+In addition to interfacing with an external locking manager, a gfs lock
+module is responsible for interacting with external cluster management
+systems.  Lock_dlm depends on user space cluster management systems found
+at the URL above.
+
+To use gfs as a local file system, no external clustering systems are
+needed, simply:
+
+  $ mkfs -t gfs2 -p lock_nolock -j 1 /dev/block_device
+  $ mount -t gfs2 /dev/block_device /dir
+
+GFS2 is not on-disk compatible with previous versions of GFS.
+
+The following man pages can be found at the URL above:
+  gfs2_mkfs	to make a filesystem
+  gfs2_fsck	to repair a filesystem
+  gfs2_grow	to expand a filesystem online
+  gfs2_jadd	to add journals to a filesystem online
+  gfs2_tool	to manipulate, examine and tune a filesystem
+  gfs2_quota	to examine and change quota values in a filesystem
+  mount.gfs2	to find mount options
+