diff mbox series

[19/29] bcache: check CACHE_SET_IO_DISABLE bit in bch_journal()

Message ID 20190614131358.2771-20-colyli@suse.de (mailing list archive)
State New, archived
Headers show
Series bcache candidate patches for Linux v5.3 | expand

Commit Message

Coly Li June 14, 2019, 1:13 p.m. UTC 
When too many I/O errors happen on cache set and CACHE_SET_IO_DISABLE
bit is set, bch_journal() may continue to work because the journaling
bkey might be still in write set yet. The caller of bch_journal() may
believe the journal still work but the truth is in-memory journal write
set won't be written into cache device any more. This behavior may
introduce potential inconsistent metadata status.

This patch checks CACHE_SET_IO_DISABLE bit at the head of bch_journal(),
if the bit is set, bch_journal() returns NULL immediately to notice
caller to know journal does not work.

Signed-off-by: Coly Li <colyli@suse.de>
---
 drivers/md/bcache/journal.c | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 7beff8884dd0..87af7c6513c5 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -867,6 +867,10 @@  atomic_t *bch_journal(struct cache_set *c,
 	struct journal_write *w;
 	atomic_t *ret;
 
+	/* No journaling if CACHE_SET_IO_DISABLE set already */
+	if (unlikely(test_bit(CACHE_SET_IO_DISABLE, &c->flags)))
+		return NULL;
+
 	if (!CACHE_SYNC(&c->sb))
 		return NULL;