Otherwise io will hung because request will only be completed if the
cmd has the flag 'NBD_CMD_INFLIGHT'.
Fixes: 07175cb1baf4 ("nbd: make sure request completion won't concurrent")
Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
drivers/block/nbd.c | 27 ++++++++++++++++++++-------
1 file changed, 20 insertions(+), 7 deletions(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index c0a787cb5153..4829868706af 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -429,6 +429,7 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
* a new connection is reconfigured or util dead timeout.
*/
if (config->socks) {
+ __set_bit(NBD_CMD_INFLIGHT, &cmd->flags);
if (cmd->index < config->num_connections) {
struct nbd_sock *nsock =
config->socks[cmd->index];
@@ -456,6 +457,8 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
* so just warn and reset the timer.
*/
struct nbd_sock *nsock = config->socks[cmd->index];
+
+ __set_bit(NBD_CMD_INFLIGHT, &cmd->flags);
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)),
@@ -756,31 +759,31 @@ static struct nbd_cmd *nbd_handle_reply(struct nbd_device *nbd, int index,
dev_err(disk_to_dev(nbd->disk), "Unexpected reply %d from different sock %d (expected %d)",
tag, index, cmd->index);
ret = -ENOENT;
- goto out;
+ goto out_reset_inflight;
}
if (cmd->cmd_cookie != nbd_handle_to_cookie(handle)) {
dev_err(disk_to_dev(nbd->disk), "Double reply on req %p, cmd_cookie %u, handle cookie %u\n",
req, cmd->cmd_cookie, nbd_handle_to_cookie(handle));
ret = -ENOENT;
- goto out;
+ goto out_reset_inflight;
}
if (cmd->status != BLK_STS_OK) {
dev_err(disk_to_dev(nbd->disk), "Command already handled %p\n",
req);
ret = -ENOENT;
- goto out;
+ goto out_reset_inflight;
}
if (test_bit(NBD_CMD_REQUEUED, &cmd->flags)) {
dev_err(disk_to_dev(nbd->disk), "Raced with timeout on req %p\n",
req);
ret = -ENOENT;
- goto out;
+ goto out_reset_inflight;
}
if (ntohl(reply->error)) {
dev_err(disk_to_dev(nbd->disk), "Other side returned error (%d)\n",
ntohl(reply->error));
cmd->status = BLK_STS_IOERR;
- goto out;
+ goto out_reset_inflight;
}
dev_dbg(nbd_to_dev(nbd), "request %p: got reply\n", req);
@@ -803,15 +806,22 @@ static struct nbd_cmd *nbd_handle_reply(struct nbd_device *nbd, int index,
*/
if (nbd_disconnected(nbd->config)) {
cmd->status = BLK_STS_IOERR;
- goto out;
+ goto out_reset_inflight;
}
ret = -EIO;
- goto out;
+ goto out_reset_inflight;
}
dev_dbg(nbd_to_dev(nbd), "request %p: got %d bytes data\n",
req, bvec.bv_len);
}
}
+out_reset_inflight:
+ if (ret)
+ /*
+ * Caller will not complete the request, thus set the flag so
+ * that it can be completed from other context.
+ */
+ __set_bit(NBD_CMD_INFLIGHT, &cmd->flags);
out:
trace_nbd_payload_received(req, handle);
mutex_unlock(&cmd->lock);
@@ -857,6 +867,9 @@ static void recv_work(struct work_struct *work)
rq = blk_mq_rq_from_pdu(cmd);
if (likely(!blk_should_fake_timeout(rq->q)))
blk_mq_complete_request(rq);
+ else
+ /* Timeout rely on this flag to complete request. */
+ __test_and_set_bit(NBD_CMD_INFLIGHT, &cmd->flags);
percpu_ref_put(&q->q_usage_counter);
}
--
2.31.1
