blk-mq: Allow requests to never expire

Some types of requests may be started that are not gauranteed to ever
complete. This adds a request flag that a driver can use so mark the
request as such.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/block/blk-timeout.c b/block/blk-timeout.c
index 56c025894cdf..246dfb16c3d9 100644
--- a/block/blk-timeout.c
+++ b/block/blk-timeout.c
@@ -190,6 +190,9 @@ void blk_add_timer(struct request *req)
         struct request_queue *q = req->q;
         unsigned long expiry;
 
+        if (req->cmd_flags & REQ_NO_TIMEOUT)
+                return;
+
         /* blk-mq has its own handler, so we don't need ->rq_timed_out_fn */
         if (!q->mq_ops && !q->rq_timed_out_fn)
                 return;