add 2.6.32 patches to use ext4 for ext2/3

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@24082 3c298f89-4303-0410-b956-a3cf2f4a3e73

3 files changed, 202 insertions, 0 deletions

diff --git a/target/linux/generic/patches-2.6.32/040-use_ext4_for_ext23.patch b/target/linux/generic/patches-2.6.32/040-use_ext4_for_ext23.patch
new file mode 100644
index 0000000000..d5824f1bdb
--- /dev/null
+++ b/target/linux/generic/patches-2.6.32/040-use_ext4_for_ext23.patch
@@ -0,0 +1,123 @@
+From 24b584240a0006ea7436cd35f5e8983eb76f1e6f Mon Sep 17 00:00:00 2001
+From: Theodore Ts'o <tytso@mit.edu>
+Date: Mon, 7 Dec 2009 14:08:51 -0500
+Subject: [PATCH] ext4: Use ext4 file system driver for ext2/ext3 file system mounts
+
+Add a new config option, CONFIG_EXT4_USE_FOR_EXT23 which if enabled,
+will cause ext4 to be used for either ext2 or ext3 file system mounts
+when ext2 or ext3 is not enabled in the configuration.
+
+This allows minimalist kernel fanatics to drop to file system drivers
+from their compiled kernel with out losing functionality.
+
+Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
+---
+ fs/ext4/Kconfig |   10 +++++++++
+ fs/ext4/super.c |   58 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ 2 files changed, 68 insertions(+), 0 deletions(-)
+
+--- a/fs/ext4/Kconfig
++++ b/fs/ext4/Kconfig
+@@ -26,6 +26,16 @@ config EXT4_FS
+ 
+ 	  If unsure, say N.
+ 
++config EXT4_USE_FOR_EXT23
++	bool "Use ext4 for ext2/ext3 file systems"
++	depends on !EXT3_FS || !EXT2_FS
++	default y
++	help
++	  Allow the ext4 file system driver code to be used for ext2 or
++	  ext3 file system mounts.  This allows users to reduce their
++	  compiled kernel size by using one file system driver for
++	  ext2, ext3, and ext4 file systems.
++
+ config EXT4_FS_XATTR
+ 	bool "Ext4 extended attributes"
+ 	depends on EXT4_FS
+--- a/fs/ext4/super.c
++++ b/fs/ext4/super.c
+@@ -3989,6 +3989,58 @@ static int ext4_get_sb(struct file_syste
+ 	return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
+ }
+ 
++#if !defined(CONTIG_EXT2_FS) && defined(CONFIG_EXT4_USE_FOR_EXT23)
++static struct file_system_type ext2_fs_type = {
++	.owner		= THIS_MODULE,
++	.name		= "ext2",
++	.get_sb		= ext4_get_sb,
++	.kill_sb	= kill_block_super,
++	.fs_flags	= FS_REQUIRES_DEV,
++};
++
++static inline void register_as_ext2(void)
++{
++	int err = register_filesystem(&ext2_fs_type);
++	if (err)
++		printk(KERN_WARNING
++		       "EXT4-fs: Unable to register as ext2 (%d)\n", err);
++}
++
++static inline void unregister_as_ext2(void)
++{
++	unregister_filesystem(&ext2_fs_type);
++}
++#else
++static inline void register_as_ext2(void) { }
++static inline void unregister_as_ext2(void) { }
++#endif
++
++#if !defined(CONTIG_EXT3_FS) && defined(CONFIG_EXT4_USE_FOR_EXT23)
++static struct file_system_type ext3_fs_type = {
++	.owner		= THIS_MODULE,
++	.name		= "ext3",
++	.get_sb		= ext4_get_sb,
++	.kill_sb	= kill_block_super,
++	.fs_flags	= FS_REQUIRES_DEV,
++};
++
++static inline void register_as_ext3(void)
++{
++	int err = register_filesystem(&ext3_fs_type);
++	if (err)
++		printk(KERN_WARNING
++		       "EXT4-fs: Unable to register as ext3 (%d)\n", err);
++}
++
++static inline void unregister_as_ext3(void)
++{
++	unregister_filesystem(&ext3_fs_type);
++}
++#else
++static inline void register_as_ext3(void) { }
++static inline void unregister_as_ext3(void) { }
++#endif
++
+ static struct file_system_type ext4_fs_type = {
+ 	.owner		= THIS_MODULE,
+ 	.name		= "ext4",
+@@ -4018,11 +4070,15 @@ static int __init init_ext4_fs(void)
+ 	err = init_inodecache();
+ 	if (err)
+ 		goto out1;
++	register_as_ext2();
++	register_as_ext3();
+ 	err = register_filesystem(&ext4_fs_type);
+ 	if (err)
+ 		goto out;
+ 	return 0;
+ out:
++	unregister_as_ext2();
++	unregister_as_ext3();
+ 	destroy_inodecache();
+ out1:
+ 	exit_ext4_xattr();
+@@ -4038,6 +4094,8 @@ out4:
+ 
+ static void __exit exit_ext4_fs(void)
+ {
++	unregister_as_ext2();
++	unregister_as_ext3();
+ 	unregister_filesystem(&ext4_fs_type);
+ 	destroy_inodecache();
+ 	exit_ext4_xattr();
diff --git a/target/linux/generic/patches-2.6.32/041-ext4_do_not_override_ext23.patch b/target/linux/generic/patches-2.6.32/041-ext4_do_not_override_ext23.patch
new file mode 100644
index 0000000000..19b5626eef
--- /dev/null
+++ b/target/linux/generic/patches-2.6.32/041-ext4_do_not_override_ext23.patch
@@ -0,0 +1,46 @@
+From a214238d3bb03723f820b0a398928d8e1637c987 Mon Sep 17 00:00:00 2001
+From: Theodore Ts'o <tytso@mit.edu>
+Date: Wed, 9 Dec 2009 21:09:58 -0500
+Subject: [PATCH] ext4: Do not override ext2 or ext3 if built they are built as modules
+
+The CONFIG_EXT4_USE_FOR_EXT23 option must not try to take over the
+ext2 or ext3 file systems if the those file system drivers are
+configured to be built as mdoules.
+
+Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
+---
+ fs/ext4/Kconfig |    2 +-
+ fs/ext4/super.c |    4 ++--
+ 2 files changed, 3 insertions(+), 3 deletions(-)
+
+--- a/fs/ext4/Kconfig
++++ b/fs/ext4/Kconfig
+@@ -28,7 +28,7 @@ config EXT4_FS
+ 
+ config EXT4_USE_FOR_EXT23
+ 	bool "Use ext4 for ext2/ext3 file systems"
+-	depends on !EXT3_FS || !EXT2_FS
++	depends on EXT3_FS=n || EXT2_FS=n
+ 	default y
+ 	help
+ 	  Allow the ext4 file system driver code to be used for ext2 or
+--- a/fs/ext4/super.c
++++ b/fs/ext4/super.c
+@@ -3989,7 +3989,7 @@ static int ext4_get_sb(struct file_syste
+ 	return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
+ }
+ 
+-#if !defined(CONTIG_EXT2_FS) && defined(CONFIG_EXT4_USE_FOR_EXT23)
++#if !defined(CONTIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
+ static struct file_system_type ext2_fs_type = {
+ 	.owner		= THIS_MODULE,
+ 	.name		= "ext2",
+@@ -4015,7 +4015,7 @@ static inline void register_as_ext2(void
+ static inline void unregister_as_ext2(void) { }
+ #endif
+ 
+-#if !defined(CONTIG_EXT3_FS) && defined(CONFIG_EXT4_USE_FOR_EXT23)
++#if !defined(CONTIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
+ static struct file_system_type ext3_fs_type = {
+ 	.owner		= THIS_MODULE,
+ 	.name		= "ext3",
diff --git a/target/linux/generic/patches-2.6.32/042-ext4_add_ext23_module_aliases.patch b/target/linux/generic/patches-2.6.32/042-ext4_add_ext23_module_aliases.patch
new file mode 100644
index 0000000000..7ac97b5010
--- /dev/null
+++ b/target/linux/generic/patches-2.6.32/042-ext4_add_ext23_module_aliases.patch
@@ -0,0 +1,33 @@
+From 51b7e3c9fbe7d22d4e355101e9a73b44fc5c9feb Mon Sep 17 00:00:00 2001
+From: Theodore Ts'o <tytso@mit.edu>
+Date: Mon, 21 Dec 2009 10:56:09 -0500
+Subject: [PATCH] ext4: add module aliases for ext2 and ext3
+
+Add module aliases for ext2 and ext3 when CONFIG_EXT4_USE_FOR_EXT23 is
+set.  This makes the existing user-space stuff like mkinitrd working
+as is.
+
+Signed-off-by: Takashi Iwai <tiwai@suse.de>
+Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
+---
+ fs/ext4/super.c |    2 ++
+ 1 files changed, 2 insertions(+), 0 deletions(-)
+
+--- a/fs/ext4/super.c
++++ b/fs/ext4/super.c
+@@ -4010,6 +4010,7 @@ static inline void unregister_as_ext2(vo
+ {
+ 	unregister_filesystem(&ext2_fs_type);
+ }
++MODULE_ALIAS("ext2");
+ #else
+ static inline void register_as_ext2(void) { }
+ static inline void unregister_as_ext2(void) { }
+@@ -4036,6 +4037,7 @@ static inline void unregister_as_ext3(vo
+ {
+ 	unregister_filesystem(&ext3_fs_type);
+ }
++MODULE_ALIAS("ext3");
+ #else
+ static inline void register_as_ext3(void) { }
+ static inline void unregister_as_ext3(void) { }