ext4: remove the journal=update mount option

The V2 journal format was introduced around ten years ago,
for ext3. It seems highly unlikely that anyone will need this
migration option for ext4.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 10ec463..09d5f32 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -144,9 +144,6 @@
 			mount the device. This will enable 'journal_checksum'
 			internally.
 
-journal=update		Update the ext4 file system's journal to the current
-			format.
-
 journal_dev=devnum	When the external journal device's major/minor numbers
 			have changed, this option allows the user to specify
 			the new journal location.  The journal device is
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 3e697ec..9420c50 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1336,8 +1336,7 @@
 	Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
 	Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
 	Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
-	Opt_journal_update, Opt_journal_dev,
-	Opt_journal_checksum, Opt_journal_async_commit,
+	Opt_journal_dev, Opt_journal_checksum, Opt_journal_async_commit,
 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
 	Opt_data_err_abort, Opt_data_err_ignore,
 	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
@@ -1379,7 +1378,6 @@
 	{Opt_commit, "commit=%u"},
 	{Opt_min_batch_time, "min_batch_time=%u"},
 	{Opt_max_batch_time, "max_batch_time=%u"},
-	{Opt_journal_update, "journal=update"},
 	{Opt_journal_dev, "journal_dev=%u"},
 	{Opt_journal_checksum, "journal_checksum"},
 	{Opt_journal_async_commit, "journal_async_commit"},
@@ -1629,19 +1627,6 @@
 			ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
 			break;
 #endif
-		case Opt_journal_update:
-			/* @@@ FIXME */
-			/* Eventually we will want to be able to create
-			   a journal file here.  For now, only allow the
-			   user to specify an existing inode to be the
-			   journal file. */
-			if (is_remount) {
-				ext4_msg(sb, KERN_ERR,
-					 "Cannot specify journal on remount");
-				return 0;
-			}
-			set_opt(sb, UPDATE_JOURNAL);
-			break;
 		case Opt_journal_dev:
 			if (is_remount) {
 				ext4_msg(sb, KERN_ERR,
@@ -4109,15 +4094,6 @@
 	if (!(journal->j_flags & JBD2_BARRIER))
 		ext4_msg(sb, KERN_INFO, "barriers disabled");
 
-	if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
-		err = jbd2_journal_update_format(journal);
-		if (err)  {
-			ext4_msg(sb, KERN_ERR, "error updating journal");
-			jbd2_journal_destroy(journal);
-			return err;
-		}
-	}
-
 	if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
 		err = jbd2_journal_wipe(journal, !really_read_only);
 	if (!err) {
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 47e3411..cfb36d9 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -71,7 +71,6 @@
 
 EXPORT_SYMBOL(jbd2_journal_init_dev);
 EXPORT_SYMBOL(jbd2_journal_init_inode);
-EXPORT_SYMBOL(jbd2_journal_update_format);
 EXPORT_SYMBOL(jbd2_journal_check_used_features);
 EXPORT_SYMBOL(jbd2_journal_check_available_features);
 EXPORT_SYMBOL(jbd2_journal_set_features);
@@ -96,7 +95,6 @@
 EXPORT_SYMBOL(jbd2_journal_begin_ordered_truncate);
 EXPORT_SYMBOL(jbd2_inode_cache);
 
-static int journal_convert_superblock_v1(journal_t *, journal_superblock_t *);
 static void __journal_abort_soft (journal_t *journal, int errno);
 static int jbd2_journal_create_slab(size_t slab_size);
 
@@ -1552,61 +1550,6 @@
 EXPORT_SYMBOL(jbd2_journal_clear_features);
 
 /**
- * int jbd2_journal_update_format () - Update on-disk journal structure.
- * @journal: Journal to act on.
- *
- * Given an initialised but unloaded journal struct, poke about in the
- * on-disk structure to update it to the most recent supported version.
- */
-int jbd2_journal_update_format (journal_t *journal)
-{
-	journal_superblock_t *sb;
-	int err;
-
-	err = journal_get_superblock(journal);
-	if (err)
-		return err;
-
-	sb = journal->j_superblock;
-
-	switch (be32_to_cpu(sb->s_header.h_blocktype)) {
-	case JBD2_SUPERBLOCK_V2:
-		return 0;
-	case JBD2_SUPERBLOCK_V1:
-		return journal_convert_superblock_v1(journal, sb);
-	default:
-		break;
-	}
-	return -EINVAL;
-}
-
-static int journal_convert_superblock_v1(journal_t *journal,
-					 journal_superblock_t *sb)
-{
-	int offset, blocksize;
-	struct buffer_head *bh;
-
-	printk(KERN_WARNING
-		"JBD2: Converting superblock from version 1 to 2.\n");
-
-	/* Pre-initialise new fields to zero */
-	offset = ((char *) &(sb->s_feature_compat)) - ((char *) sb);
-	blocksize = be32_to_cpu(sb->s_blocksize);
-	memset(&sb->s_feature_compat, 0, blocksize-offset);
-
-	sb->s_nr_users = cpu_to_be32(1);
-	sb->s_header.h_blocktype = cpu_to_be32(JBD2_SUPERBLOCK_V2);
-	journal->j_format_version = 2;
-
-	bh = journal->j_sb_buffer;
-	BUFFER_TRACE(bh, "marking dirty");
-	mark_buffer_dirty(bh);
-	sync_dirty_buffer(bh);
-	return 0;
-}
-
-
-/**
  * int jbd2_journal_flush () - Flush journal
  * @journal: Journal to act on.
  *