@@ -930,12 +930,12 @@ restart_loop:
/* A buffer which has been freed while still being
* journaled by a previous transaction may end up still
* being dirty here, but we want to avoid writing back
- * that buffer in the future now that the last use has
- * been committed. That's not only a performance gain,
- * it also stops aliasing problems if the buffer is left
- * behind for writeback and gets reallocated for another
+ * that buffer in the future after the "add to orphan"
+ * operation been committed, That's not only a performance
+ * gain, it also stops aliasing problems if the buffer is
+ * left behind for writeback and gets reallocated for another
* use in a different page. */
- if (buffer_freed(bh)) {
+ if (buffer_freed(bh) && !jh->b_next_transaction) {
clear_buffer_freed(bh);
clear_buffer_jbddirty(bh);
}
@@ -1783,16 +1783,20 @@ static int journal_unmap_buffer(journal_t *journal, struct buffer_head *bh)
} else if (transaction == journal->j_committing_transaction) {
JBUFFER_TRACE(jh, "on committing transaction");
/*
- * If it is committing, we simply cannot touch it. We
- * can remove it's next_transaction pointer from the
- * running transaction if that is set, but nothing
- * else. */
+ * We don't know the transaction which "add to orphan" handle
+ * belongs to, there are three cases:
+ * (1) it's a transaction which has been committed
+ * (2) it's the committing transaction
+ * (3) it's the running transaction
+ * We can't clear the BH_jbddirty bit and discard the buffer
+ * before "add to orphan" has been committed, just
+ * be conservative, if running transaction exists and buffer
+ * has been dirtied(may be by previous transaction), wait until
+ * running transaction complete commit and do the discard work.
+ */
set_buffer_freed(bh);
- if (jh->b_next_transaction) {
- J_ASSERT(jh->b_next_transaction ==
- journal->j_running_transaction);
- jh->b_next_transaction = NULL;
- }
+ if (journal->j_running_transaction && buffer_jbddirty(bh))
+ jh->b_next_transaction = journal->j_running_transaction;
jbd2_journal_put_journal_head(jh);
spin_unlock(&journal->j_list_lock);
jbd_unlock_bh_state(bh);
@@ -1969,7 +1973,7 @@ void jbd2_journal_file_buffer(struct journal_head *jh,
*/
void __jbd2_journal_refile_buffer(struct journal_head *jh)
{
- int was_dirty;
+ int was_dirty, jlist;
struct buffer_head *bh = jh2bh(jh);
J_ASSERT_JH(jh, jbd_is_locked_bh_state(bh));
@@ -1991,8 +1995,13 @@ void __jbd2_journal_refile_buffer(struct journal_head *jh)
__jbd2_journal_temp_unlink_buffer(jh);
jh->b_transaction = jh->b_next_transaction;
jh->b_next_transaction = NULL;
- __jbd2_journal_file_buffer(jh, jh->b_transaction,
- jh->b_modified ? BJ_Metadata : BJ_Reserved);
+ if (buffer_freed(bh))
+ jlist = BJ_Forget;
+ else if (jh->b_modified)
+ jlist = BJ_Metadata;
+ else
+ jlist = BJ_Reserved;
+ __jbd2_journal_file_buffer(jh, jh->b_transaction, jlist);
J_ASSERT_JH(jh, jh->b_transaction->t_state == T_RUNNING);
if (was_dirty)