For the upcoming async polled IO, we can't sleep allocating requests.
If we do, then we introduce a deadlock where the submitter already
has async polled IO in-flight, but can't wait for them to complete
since polled requests must be active found and reaped.
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
include/linux/blk_types.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 46c005d601ac..921d734d6b5d 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -347,6 +347,7 @@ enum req_flag_bits {
#define REQ_NOWAIT (1ULL << __REQ_NOWAIT)
#define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP)
#define REQ_HIPRI (1ULL << __REQ_HIPRI)
+#define REQ_HIPRI_ASYNC (REQ_HIPRI | REQ_NOWAIT)
#define REQ_DRV (1ULL << __REQ_DRV)
#define REQ_SWAP (1ULL << __REQ_SWAP)
--
2.17.1
