In commit 2da22da5734 (nbd: fix zero cmd timeout handling v2),
it is allowed to reset timer when it fires if tag_set.timeout
is set to zero. If the server is shutdown and a new socket
is reconfigured, the request should be requeued to be processed by
new server instead of waiting for response from the old one.
Signed-off-by: Hou Pu <houpu@xxxxxxxxxxxxx>
---
drivers/block/nbd.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 8e348c9c49a4..7bbc5477066c 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -434,12 +434,22 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
* Userspace sets timeout=0 to disable socket disconnection,
* so just warn and reset the timer.
*/
+ struct nbd_sock *nsock = config->socks[cmd->index];
cmd->retries++;
dev_info(nbd_to_dev(nbd), "Possible stuck request %p: control (%s@%llu,%uB). Runtime %u seconds\n",
req, nbdcmd_to_ascii(req_to_nbd_cmd_type(req)),
(unsigned long long)blk_rq_pos(req) << 9,
blk_rq_bytes(req), (req->timeout / HZ) * cmd->retries);
+ mutex_lock(&nsock->tx_lock);
+ if (cmd->cookie != nsock->cookie) {
+ nbd_requeue_cmd(cmd);
+ mutex_unlock(&nsock->tx_lock);
+ mutex_unlock(&cmd->lock);
+ nbd_config_put(nbd);
+ return BLK_EH_DONE;
+ }
+ mutex_unlock(&nsock->tx_lock);
mutex_unlock(&cmd->lock);
nbd_config_put(nbd);
return BLK_EH_RESET_TIMER;
--
2.11.0
