[U-Boot] [PATCH] ext4: add support for filesystems without JOURNAL

[Marek Szyprowski]

JOURNAL is optional for EXT4 (and EXT3) filesystems, so add support for
skipping it. This fixes corrupting EXT4 volumes without JOURNAL after
using uboot's 'ext4write' command.

Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
---
 fs/ext4/ext4_journal.c | 4 ++++
 fs/ext4/ext4_journal.h | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/fs/ext4/ext4_journal.c b/fs/ext4/ext4_journal.c
index 6adbab93a68..3559daf11d2 100644
--- a/fs/ext4/ext4_journal.c
+++ b/fs/ext4/ext4_journal.c
@@ -645,6 +645,10 @@ void ext4fs_update_journal(void)
 	struct ext_filesystem *fs = get_fs();
 	long int blknr;
 	int i;
+
+	if (!(fs->sb->feature_compatibility & EXT4_FEATURE_COMPAT_HAS_JOURNAL))
+		return;
+
 	ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO, &inode_journal);
 	blknr = read_allocated_block(&inode_journal, jrnl_blk_idx++, NULL);
 	update_descriptor_block(blknr);
diff --git a/fs/ext4/ext4_journal.h b/fs/ext4/ext4_journal.h
index c9cf195f333..43fb8e76641 100644
--- a/fs/ext4/ext4_journal.h
+++ b/fs/ext4/ext4_journal.h
@@ -17,6 +17,8 @@
 #ifndef __EXT4_JRNL__
 #define __EXT4_JRNL__
 
+#define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
+
 #define EXT2_JOURNAL_INO		8	/* Journal inode */
 #define EXT2_JOURNAL_SUPERBLOCK	0	/* Journal  Superblock number */
 
-- 
2.17.1