[PATCH 4.10 09/27] md/r5cache: fix set_syndrome_sources() for data in cache

Greg Kroah-Hartman
2017-03-24T18:09:31Z

From: Song Liu <songliubraving@fb.com>

commit 0977762f6d15f13caccc20d71a5dec47d098907d upstream.

Before this patch, device InJournal will be included in prexor
(SYNDROME_SRC_WANT_DRAIN) but not in reconstruct (SYNDROME_SRC_WRITTEN). So it
will break parity calculation. With srctype == SYNDROME_SRC_WRITTEN, we need
include both dev with non-null ->written and dev with R5_InJournal. This fixes
logic in 1e6d690(md/r5cache: caching phase of r5cache)

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/md/raid5.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1364,7 +1364,8 @@ static int set_syndrome_sources(struct p
(test_bit(R5_Wantdrain, &dev->flags) ||
test_bit(R5_InJournal, &dev->flags))) ||
(srctype == SYNDROME_SRC_WRITTEN &&
- dev->written)) {
+ (dev->written ||
+ test_bit(R5_InJournal, &dev->flags)))) {
if (test_bit(R5_InJournal, &dev->flags))
srcs[slot] = sh->dev[i].orig_page;
else