From: Eric Sandeen <sandeen@redhat.com>
Date: Thu, 21 Aug 2008 15:46:30 -0500
Subject: [fs] ext4: Kconfig/Makefile/config glue
Message-id: 48ADD426.9000705@redhat.com
O-Subject: [RHEL5.3 Patch 6/6] ext4: Kconfig/Makefile/config glue
Bugzilla: 458718

[Bug 458718] FEAT: RHEL 5.3 ext4 tech preview

Add upstream Kconfig & Makefile bits, and turn on ext4/jbd2 for generic.

diff --git a/fs/Kconfig b/fs/Kconfig
index 8a33980..b8235ce 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -138,6 +138,72 @@ config EXT3_FS_SECURITY
 	  If you are not using a security module that requires using
 	  extended attributes for file security labels, say N.
 
+config EXT4DEV_FS
+	tristate "Ext4dev/ext4 extended fs support development (EXPERIMENTAL)"
+	depends on EXPERIMENTAL
+	select JBD2
+	select CRC16
+	help
+	  Ext4dev is a predecessor filesystem of the next generation
+	  extended fs ext4, based on ext3 filesystem code. It will be
+	  renamed ext4 fs later, once ext4dev is mature and stabilized.
+
+	  Unlike the change from ext2 filesystem to ext3 filesystem,
+	  the on-disk format of ext4dev is not the same as ext3 any more:
+	  it is based on extent maps and it supports 48-bit physical block
+	  numbers. These combined on-disk format changes will allow
+	  ext4dev/ext4 to handle more than 16 TB filesystem volumes --
+	  a hard limit that ext3 cannot overcome without changing the
+	  on-disk format.
+
+	  Other than extent maps and 48-bit block numbers, ext4dev also is
+	  likely to have other new features such as persistent preallocation,
+	  high resolution time stamps, and larger file support etc.  These
+	  features will be added to ext4dev gradually.
+
+	  To compile this file system support as a module, choose M here. The
+	  module will be called ext4dev.
+
+	  If unsure, say N.
+
+config EXT4DEV_FS_XATTR
+	bool "Ext4dev extended attributes"
+	depends on EXT4DEV_FS
+	default y
+	help
+	  Extended attributes are name:value pairs associated with inodes by
+	  the kernel or by users (see the attr(5) manual page, or visit
+	  <http://acl.bestbits.at/> for details).
+
+	  If unsure, say N.
+
+	  You need this for POSIX ACL support on ext4dev/ext4.
+
+config EXT4DEV_FS_POSIX_ACL
+	bool "Ext4dev POSIX Access Control Lists"
+	depends on EXT4DEV_FS_XATTR
+	select FS_POSIX_ACL
+	help
+	  POSIX Access Control Lists (ACLs) support permissions for users and
+	  groups beyond the owner/group/world scheme.
+
+	  To learn more about Access Control Lists, visit the POSIX ACLs for
+	  Linux website <http://acl.bestbits.at/>.
+
+	  If you don't know what Access Control Lists are, say N
+
+config EXT4DEV_FS_SECURITY
+	bool "Ext4dev Security Labels"
+	depends on EXT4DEV_FS_XATTR
+	help
+	  Security labels support alternative access control models
+	  implemented by security modules like SELinux.  This option
+	  enables an extended attribute handler for file security
+	  labels in the ext4dev/ext4 filesystem.
+
+	  If you are not using a security module that requires using
+	  extended attributes for file security labels, say N.
+
 config JBD
 	tristate
 	help
@@ -170,6 +236,39 @@ config JBD_DEBUG
 	  generated.  To turn debugging off again, do
 	  "echo 0 > /proc/sys/fs/jbd-debug".
 
+config JBD2
+	tristate
+	select CRC32
+	help
+	  This is a generic journaling layer for block devices that support
+	  both 32-bit and 64-bit block numbers.  It is currently used by
+	  the ext4dev/ext4 filesystem, but it could also be used to add
+	  journal support to other file systems or block devices such
+	  as RAID or LVM.
+
+	  If you are using ext4dev/ext4, you need to say Y here. If you are not
+	  using ext4dev/ext4 then you will probably want to say N.
+
+	  To compile this device as a module, choose M here. The module will be
+	  called jbd2.  If you are compiling ext4dev/ext4 into the kernel,
+	  you cannot compile this code as a module.
+
+config JBD2_DEBUG
+	bool "JBD2 (ext4dev/ext4) debugging support"
+	depends on JBD2 && DEBUG_FS
+	help
+	  If you are using the ext4dev/ext4 journaled file system (or
+	  potentially any other filesystem/device using JBD2), this option
+	  allows you to enable debugging output while the system is running,
+	  in order to help track down any problems you are having.
+	  By default, the debugging output will be turned off.
+
+	  If you select Y here, then you will be able to turn on debugging
+	  with "echo N > /sys/kernel/debug/jbd2/jbd2-debug", where N is a
+	  number between 1 and 5. The higher the number, the more debugging
+	  output is generated.  To turn debugging off again, do
+	  "echo 0 > /sys/kernel/debug/jbd2/jbd2-debug".
+
 config FS_MBCACHE
 # Meta block cache for Extended Attributes (ext2/ext3)
 	tristate
diff --git a/fs/Makefile b/fs/Makefile
index 6bc3688..4e3ee3d 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -58,7 +58,9 @@ obj-$(CONFIG_DLM)		+= dlm/
 obj-$(CONFIG_FSCACHE)		+= fscache/
 obj-$(CONFIG_REISERFS_FS)	+= reiserfs/
 obj-$(CONFIG_EXT3_FS)		+= ext3/ # Before ext2 so root fs can be ext3
+obj-$(CONFIG_EXT4DEV_FS)	+= ext4/ # Before ext2 so root fs can be ext4dev
 obj-$(CONFIG_JBD)		+= jbd/
+obj-$(CONFIG_JBD2)		+= jbd2/
 obj-$(CONFIG_EXT2_FS)		+= ext2/
 obj-$(CONFIG_CRAMFS)		+= cramfs/
 obj-$(CONFIG_SQUASHFS)		+= squashfs/