jbd: clear revoked flag on buffers before a new transaction started

Currently, we clear revoked flag only when a block is reused.  However,
this can tigger a false journal error.  Consider a situation when a block
is used as a meta block and is deleted(revoked) in ordered mode, then the
block is allocated as a data block to a file.  At this moment, user changes
the file's journal mode from ordered to journaled and truncates the file.
The block will be considered re-revoked by journal because it has revoked
flag still pending from the last transaction and an assertion triggers.

We fix the problem by keeping the revoked status more uptodate - we clear
revoked flag when switching revoke tables to reflect there is no revoked
buffers in current transaction any more.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/jbd.h b/include/linux/jbd.h
index c7acdde3243d..492cc12244fd 100644
--- a/include/linux/jbd.h
+++ b/include/linux/jbd.h
@@ -913,6 +913,7 @@ extern int	journal_set_revoke(journal_t *, unsigned int, tid_t);
 extern int      journal_test_revoke(journal_t *, unsigned int, tid_t);
 extern void     journal_clear_revoke(journal_t *);
 extern void     journal_switch_revoke_table(journal_t *journal);
+extern void     journal_clear_buffer_revoked_flags(journal_t *journal);
 
 /*
  * The log thread user interface: