From 82a9c16a10521a0ceadbd27a549f6e8d5e70e0ab Mon Sep 17 00:00:00 2001 From: Sean Hefty Date: Wed, 4 Oct 2006 11:37:25 -0700 Subject: [PATCH] IB/cm: Send DREP in response to unmatched DREQ Currently a DREP is only sent in response to a DREQ if a connection has been found matching the DREQ, and it is in the proper state. Once a DREP is sent, the local connection moves into timewait. Duplicate DREQs received while in this state result in re-sending the DREP. However, it's likely that the local connection will enter and exit timewait before the remote side times out a lost DREP and resends a DREQ. To handle this, we send a DREP in response to a DREQ, even if a local connection is not found. This avoids maintaining disconnected id's in timewait states for excessively long times, just to handle a lost DREP. Signed-off-by: Sean Hefty Signed-off-by: Roland Dreier --- drivers/infiniband/core/cm.c | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c index 470c482f2887..25b1018a476c 100644 --- a/drivers/infiniband/core/cm.c +++ b/drivers/infiniband/core/cm.c @@ -1902,6 +1902,32 @@ out: spin_unlock_irqrestore(&cm_id_priv->lock, flags); } EXPORT_SYMBOL(ib_send_cm_drep); +static int cm_issue_drep(struct cm_port *port, + struct ib_mad_recv_wc *mad_recv_wc) +{ + struct ib_mad_send_buf *msg = NULL; + struct cm_dreq_msg *dreq_msg; + struct cm_drep_msg *drep_msg; + int ret; + + ret = cm_alloc_response_msg(port, mad_recv_wc, &msg); + if (ret) + return ret; + + dreq_msg = (struct cm_dreq_msg *) mad_recv_wc->recv_buf.mad; + drep_msg = (struct cm_drep_msg *) msg->mad; + + cm_format_mad_hdr(&drep_msg->hdr, CM_DREP_ATTR_ID, dreq_msg->hdr.tid); + drep_msg->remote_comm_id = dreq_msg->local_comm_id; + drep_msg->local_comm_id = dreq_msg->remote_comm_id; + + ret = ib_post_send_mad(msg, NULL); + if (ret) + cm_free_msg(msg); + + return ret; +} + static int cm_dreq_handler(struct cm_work *work) { struct cm_id_private *cm_id_priv; @@ -1913,8 +1939,10 @@ static int cm_dreq_handler(struct cm_work *work) dreq_msg = (struct cm_dreq_msg *)work->mad_recv_wc->recv_buf.mad; cm_id_priv = cm_acquire_id(dreq_msg->remote_comm_id, dreq_msg->local_comm_id); - if (!cm_id_priv) + if (!cm_id_priv) { + cm_issue_drep(work->port, work->mad_recv_wc); return -EINVAL; + } work->cm_event.private_data = &dreq_msg->private_data; -- 2.30.2