ext4, jbd2: add REQ_FUA flag when recording an error in the superblock
When an error condition is detected, an error status should be recorded into
superblocks of EXT4 or JBD2. However, the write request is submitted now
without REQ_FUA flag, even in "barrier=1" mode, which is followed by
panic() function in "errors=panic" mode. On mobile devices which make
whole system reset as soon as kernel panic occurs, this write request
containing an error flag will disappear just from storage cache without
written to the physical cells. Therefore, when next start, even forever,
the error flag cannot be shown in both superblocks, and e2fsck cannot fix
the filesystem problems automatically, unless e2fsck is executed in
force checking mode.
[ Changed use test_opt(sb, BARRIER) of checking the journal flags -- TYT ]
Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 14909cd..a51db9c 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4667,7 +4667,8 @@
ext4_superblock_csum_set(sb);
mark_buffer_dirty(sbh);
if (sync) {
- error = sync_dirty_buffer(sbh);
+ error = __sync_dirty_buffer(sbh,
+ test_opt(sb, BARRIER) ? WRITE_FUA : WRITE_SYNC);
if (error)
return error;
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 4ff3fad..fe1b4bd 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -1456,7 +1456,7 @@
sb->s_errno = cpu_to_be32(journal->j_errno);
read_unlock(&journal->j_state_lock);
- jbd2_write_superblock(journal, WRITE_SYNC);
+ jbd2_write_superblock(journal, WRITE_FUA);
}
EXPORT_SYMBOL(jbd2_journal_update_sb_errno);