jbd2_journal_flush
err = jbd2_journal_flush(journal, 0);
err = jbd2_journal_flush(EXT4_SB(sb)->s_journal, flush_flags);
err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal, 0);
err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal, 0);
err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal, 0);
err = jbd2_journal_flush(journal, 0);
error = jbd2_journal_flush(journal, 0);
EXPORT_SYMBOL(jbd2_journal_flush);
status = jbd2_journal_flush(journal->j_journal, 0);
status = jbd2_journal_flush(journal->j_journal, 0);
status = jbd2_journal_flush(journal->j_journal, 0);
status = jbd2_journal_flush(journal, 0);
status = jbd2_journal_flush(journal->j_journal, 0);
extern int jbd2_journal_flush(journal_t *journal, unsigned int flags);