For an atomic writes, a cloned bio must be same length as the original bio,
i.e. no splitting.
Error in case it is not.
Per-dm device queue limits should be setup to ensure that this does not
happen, but error this case as an insurance policy.
Signed-off-by: John Garry <john.g.garry@xxxxxxxxxx>
---
drivers/md/dm.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 12ecf07a3841..e26c73fb365a 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1746,6 +1746,9 @@ static blk_status_t __split_and_process_bio(struct clone_info *ci)
ci->submit_as_polled = !!(ci->bio->bi_opf & REQ_POLLED);
len = min_t(sector_t, max_io_len(ti, ci->sector), ci->sector_count);
+ if (ci->bio->bi_opf & REQ_ATOMIC && len != ci->sector_count)
+ return BLK_STS_IOERR;
+
setup_split_accounting(ci, len);
if (unlikely(ci->bio->bi_opf & REQ_NOWAIT)) {
--
2.31.1
