Commit b685d3d65ac7 "block: treat REQ_FUA and REQ_PREFLUSH as
synchronous" removed REQ_SYNC flag from WRITE_{FUA|PREFLUSH|...}
definitions. generic_make_request_checks() however strips REQ_FUA and
REQ_PREFLUSH flags from a bio when the storage doesn't report volatile
write cache and thus write effectively becomes asynchronous which can
lead to performance regressions
Fix the problem by making sure all bios which are synchronous are
properly marked with REQ_SYNC.
CC: linux-raid@xxxxxxxxxxxxxxx
CC: Shaohua Li <shli@xxxxxxxxxx>
Fixes: b685d3d65ac791406e0dfd8779cc9b3707fea5a3
CC: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
drivers/md/md.c | 2 +-
drivers/md/raid5-cache.c | 4 ++--
drivers/md/raid5-ppl.c | 4 ++--
3 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 10367ffe92e3..212a6777ff31 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -765,7 +765,7 @@ void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
test_bit(FailFast, &rdev->flags) &&
!test_bit(LastDev, &rdev->flags))
ff = MD_FAILFAST;
- bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_FUA | ff;
+ bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH | REQ_FUA | ff;
atomic_inc(&mddev->pending_writes);
submit_bio(bio);
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index 4c00bc248287..0a7af8b0a80a 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -1782,7 +1782,7 @@ static int r5l_log_write_empty_meta_block(struct r5l_log *log, sector_t pos,
mb->checksum = cpu_to_le32(crc32c_le(log->uuid_checksum,
mb, PAGE_SIZE));
if (!sync_page_io(log->rdev, pos, PAGE_SIZE, page, REQ_OP_WRITE,
- REQ_FUA, false)) {
+ REQ_SYNC | REQ_FUA, false)) {
__free_page(page);
return -EIO;
}
@@ -2388,7 +2388,7 @@ r5c_recovery_rewrite_data_only_stripes(struct r5l_log *log,
mb->checksum = cpu_to_le32(crc32c_le(log->uuid_checksum,
mb, PAGE_SIZE));
sync_page_io(log->rdev, ctx->pos, PAGE_SIZE, page,
- REQ_OP_WRITE, REQ_FUA, false);
+ REQ_OP_WRITE, REQ_SYNC | REQ_FUA, false);
sh->log_start = ctx->pos;
list_add_tail(&sh->r5c, &log->stripe_in_journal_list);
atomic_inc(&log->stripe_in_journal_count);
diff --git a/drivers/md/raid5-ppl.c b/drivers/md/raid5-ppl.c
index 5d25bebf3328..ccce92e68d7f 100644
--- a/drivers/md/raid5-ppl.c
+++ b/drivers/md/raid5-ppl.c
@@ -907,8 +907,8 @@ static int ppl_write_empty_header(struct ppl_log *log)
pplhdr->checksum = cpu_to_le32(~crc32c_le(~0, pplhdr, PAGE_SIZE));
if (!sync_page_io(rdev, rdev->ppl.sector - rdev->data_offset,
- PPL_HEADER_SIZE, page, REQ_OP_WRITE | REQ_FUA, 0,
- false)) {
+ PPL_HEADER_SIZE, page, REQ_OP_WRITE | REQ_SYNC |
+ REQ_FUA, 0, false)) {
md_error(rdev->mddev, rdev);
ret = -EIO;
}
--
2.12.3