[PATCH 16/16] fuse2fs: spot check clean journals

["Darrick J. Wong" <djwong@kernel.org>]

From: Darrick J. Wong <djwong@kernel.org>

Even though fuse2fs doesn't (yet) support writing new transactions to
the journal, we ought at least to check that the superblock is ok when
we mount a clean filesystem.  This fixes complaints by ext4/012 about
mount failing to notice a corrupt journal.

Cc: <linux-ext4@vger.kernel.org> # v1.43
Fixes: 81cbf1ef4f5dab ("misc: add fuse2fs, a FUSE server for e2fsprogs")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
---
 debugfs/journal.h |    2 ++
 debugfs/journal.c |    2 +-
 misc/fuse2fs.c    |    7 +++++++
 3 files changed, 10 insertions(+), 1 deletion(-)


diff --git a/debugfs/journal.h b/debugfs/journal.h
index 10b638ebaab5db..67b8c99828bb0d 100644
--- a/debugfs/journal.h
+++ b/debugfs/journal.h
@@ -18,6 +18,8 @@
 errcode_t ext2fs_open_journal(ext2_filsys fs, journal_t **j);
 errcode_t ext2fs_close_journal(ext2_filsys fs, journal_t **j);
 errcode_t ext2fs_run_ext3_journal(ext2_filsys *fs);
+errcode_t ext2fs_check_ext3_journal(ext2_filsys fs);
+
 void jbd2_commit_block_csum_set(journal_t *j, struct buffer_head *bh);
 void jbd2_revoke_csum_set(journal_t *j, struct buffer_head *bh);
 void jbd2_descr_block_csum_set(journal_t *j, struct buffer_head *bh);
diff --git a/debugfs/journal.c b/debugfs/journal.c
index a6d8d4c5adf9cf..f79abcccf6adea 100644
--- a/debugfs/journal.c
+++ b/debugfs/journal.c
@@ -681,7 +681,7 @@ static void ext2fs_journal_release(ext2_filsys fs, journal_t *journal,
  * This function makes sure that the superblock fields regarding the
  * journal are consistent.
  */
-static errcode_t ext2fs_check_ext3_journal(ext2_filsys fs)
+errcode_t ext2fs_check_ext3_journal(ext2_filsys fs)
 {
 	struct ext2_super_block *sb = fs->super;
 	journal_t *journal;
diff --git a/misc/fuse2fs.c b/misc/fuse2fs.c
index 210807ea493f51..e33b09de08a11f 100644
--- a/misc/fuse2fs.c
+++ b/misc/fuse2fs.c
@@ -192,6 +192,7 @@ static inline uint64_t round_down(uint64_t b, unsigned int align)
 # define FL_ZERO_RANGE_FLAG (0)
 #endif
 
+errcode_t ext2fs_check_ext3_journal(ext2_filsys fs);
 errcode_t ext2fs_run_ext3_journal(ext2_filsys *fs);
 
 #ifdef CONFIG_JBD_DEBUG		/* Enabled by configure --enable-jbd-debug */
@@ -4819,6 +4820,12 @@ int main(int argc, char *argv[])
 			ext2fs_clear_feature_journal_needs_recovery(global_fs->super);
 			ext2fs_mark_super_dirty(global_fs);
 		}
+	} else if (ext2fs_has_feature_journal(global_fs->super)) {
+		err = ext2fs_check_ext3_journal(global_fs);
+		if (err) {
+			translate_error(global_fs, 0, err);
+			goto out;
+		}
 	}
 
 	if (global_fs->flags & EXT2_FLAG_RW) {