fs: Remove ext3 filesystem driver

The functionality of ext3 is fully supported by ext4 driver. Major
distributions (SUSE, RedHat) already use ext4 driver to handle ext3
filesystems for quite some time. There is some ugliness in mm resulting
from jbd cleaning buffers in a dirty page without cleaning page dirty
bit and also support for buffer bouncing in the block layer when stable
pages are required is there only because of jbd. So let's remove the
ext3 driver. This saves us some 28k lines of duplicated code.

Acked-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>

2 files changed, 39 insertions, 16 deletions

diff --git a/fs/ext4/Kconfig b/fs/ext4/Kconfig
index bf8bc8aba471..219a190ccae9 100644
--- a/fs/ext4/Kconfig
+++ b/fs/ext4/Kconfig
@@ -1,5 +1,38 @@
+# Ext3 configs are here for backward compatibility with old configs which may
+# have EXT3_FS set but not EXT4_FS set and thus would result in non-bootable
+# kernels after the removal of ext3 driver.
+config EXT3_FS
+	tristate "The Extended 3 (ext3) filesystem"
+	# These must match EXT4_FS selects...
+	select EXT4_FS
+	select JBD2
+	select CRC16
+	select CRYPTO
+	select CRYPTO_CRC32C
+	help
+	  This config option is here only for backward compatibility. ext3
+	  filesystem is now handled by the ext4 driver.
+
+config EXT3_FS_POSIX_ACL
+	bool "Ext3 POSIX Access Control Lists"
+	depends on EXT3_FS
+	select EXT4_FS_POSIX_ACL
+	select FS_POSIX_ACL
+	help
+	  This config option is here only for backward compatibility. ext3
+	  filesystem is now handled by the ext4 driver.
+
+config EXT3_FS_SECURITY
+	bool "Ext3 Security Labels"
+	depends on EXT3_FS
+	select EXT4_FS_SECURITY
+	help
+	  This config option is here only for backward compatibility. ext3
+	  filesystem is now handled by the ext4 driver.
+
 config EXT4_FS
 	tristate "The Extended 4 (ext4) filesystem"
+	# Please update EXT3_FS selects when changing these
 	select JBD2
 	select CRC16
 	select CRYPTO
@@ -28,14 +61,14 @@ config EXT4_FS
 
 	  If unsure, say N.
 
-config EXT4_USE_FOR_EXT23
+config EXT4_USE_FOR_EXT2
 	bool "Use ext4 for ext2/ext3 file systems"
 	depends on EXT4_FS
-	depends on EXT3_FS=n || EXT2_FS=n
+	depends on EXT2_FS=n
 	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
+	  Allow the ext4 file system driver code to be used for ext2
+	  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.
 
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 58987b5c514b..06b4b14e8aa0 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -84,7 +84,7 @@ static void ext4_unregister_li_request(struct super_block *sb);
 static void ext4_clear_request_list(void);
 static int ext4_reserve_clusters(struct ext4_sb_info *, ext4_fsblk_t);
 
-#if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
+#if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 static struct file_system_type ext2_fs_type = {
 	.owner		= THIS_MODULE,
 	.name		= "ext2",
@@ -100,7 +100,6 @@ MODULE_ALIAS("ext2");
 #endif
 
 
-#if !defined(CONFIG_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",
@@ -111,9 +110,6 @@ static struct file_system_type ext3_fs_type = {
 MODULE_ALIAS_FS("ext3");
 MODULE_ALIAS("ext3");
 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
-#else
-#define IS_EXT3_SB(sb) (0)
-#endif
 
 static int ext4_verify_csum_type(struct super_block *sb,
 				 struct ext4_super_block *es)
@@ -5500,7 +5496,7 @@ static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
 	return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
 }
 
-#if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
+#if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 static inline void register_as_ext2(void)
 {
 	int err = register_filesystem(&ext2_fs_type);
@@ -5530,7 +5526,6 @@ static inline void unregister_as_ext2(void) { }
 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
 #endif
 
-#if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
 static inline void register_as_ext3(void)
 {
 	int err = register_filesystem(&ext3_fs_type);
@@ -5556,11 +5551,6 @@ static inline int ext3_feature_set_ok(struct super_block *sb)
 		return 0;
 	return 1;
 }
-#else
-static inline void register_as_ext3(void) { }
-static inline void unregister_as_ext3(void) { }
-static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
-#endif
 
 static struct file_system_type ext4_fs_type = {
 	.owner		= THIS_MODULE,