[PATCH 3.14 074/110] Target/iser: Improve cm events handling

Greg Kroah-Hartman
2014-06-28T18:38:52Z

From: Sagi Grimberg <sagig@mellanox.com>

commit 88c4015fda6d014392f76d3b1688347950d7a12d upstream.

There are 4 RDMA_CM events that all basically mean that
the user should teardown the IB connection:
- DISCONNECTED
- ADDR_CHANGE
- DEVICE_REMOVAL
- TIMEWAIT_EXIT

Only in DISCONNECTED/ADDR_CHANGE it makes sense to
call rdma_disconnect (send DREQ/DREP to our initiator).
So we keep the same teardown handler for all of them
but only indicate calling rdma_disconnect for the relevant
events.

This patch also removes redundant debug prints for each single
event.

v2 changes:
- Call isert_disconnected_handler() for DEVICE_REMOVAL (Or + Sag)

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/infiniband/ulp/isert/ib_isert.c | 26 ++++++++++++++------------
drivers/infiniband/ulp/isert/ib_isert.h | 1 +
2 files changed, 15 insertions(+), 12 deletions(-)

--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -706,8 +706,10 @@ isert_disconnect_work(struct work_struct
return;
}

- /* Send DREQ/DREP towards our initiator */
- rdma_disconnect(isert_conn->conn_cm_id);
+ if (isert_conn->disconnect) {
+ /* Send DREQ/DREP towards our initiator */
+ rdma_disconnect(isert_conn->conn_cm_id);
+ }

mutex_unlock(&isert_conn->conn_mutex);

@@ -717,10 +719,11 @@ wake_up:
}

static void
-isert_disconnected_handler(struct rdma_cm_id *cma_id)
+isert_disconnected_handler(struct rdma_cm_id *cma_id, bool disconnect)
{
struct isert_conn *isert_conn = (struct isert_conn *)cma_id->context;

+ isert_conn->disconnect = disconnect;
INIT_WORK(&isert_conn->conn_logout_work, isert_disconnect_work);
schedule_work(&isert_conn->conn_logout_work);
}
@@ -729,29 +732,28 @@ static int
isert_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
{
int ret = 0;
+ bool disconnect = false;

pr_debug("isert_cma_handler: event %d status %d conn %p id %p\n",
event->event, event->status, cma_id->context, cma_id);

switch (event->event) {
case RDMA_CM_EVENT_CONNECT_REQUEST:
- pr_debug("RDMA_CM_EVENT_CONNECT_REQUEST: >>>>>>>>>>>>>>>\n");
ret = isert_connect_request(cma_id, event);
break;
case RDMA_CM_EVENT_ESTABLISHED:
- pr_debug("RDMA_CM_EVENT_ESTABLISHED >>>>>>>>>>>>>>\n");
isert_connected_handler(cma_id);
break;
- case RDMA_CM_EVENT_DISCONNECTED:
- pr_debug("RDMA_CM_EVENT_DISCONNECTED: >>>>>>>>>>>>>>\n");
- isert_disconnected_handler(cma_id);
- break;
- case RDMA_CM_EVENT_DEVICE_REMOVAL:
- case RDMA_CM_EVENT_ADDR_CHANGE:
+ case RDMA_CM_EVENT_ADDR_CHANGE: /* FALLTHRU */
+ case RDMA_CM_EVENT_DISCONNECTED: /* FALLTHRU */
+ case RDMA_CM_EVENT_DEVICE_REMOVAL: /* FALLTHRU */
+ disconnect = true;
+ case RDMA_CM_EVENT_TIMEWAIT_EXIT: /* FALLTHRU */
+ isert_disconnected_handler(cma_id, disconnect);
break;
case RDMA_CM_EVENT_CONNECT_ERROR:
default:
- pr_err("Unknown RDMA CMA event: %d\n", event->event);
+ pr_err("Unhandled RDMA CMA event: %d\n", event->event);
break;
}

--- a/drivers/infiniband/ulp/isert/ib_isert.h
+++ b/drivers/infiniband/ulp/isert/ib_isert.h
@@ -127,6 +127,7 @@ struct isert_conn {
#define ISERT_COMP_BATCH_COUNT 8
int conn_comp_batch;
struct llist_head conn_comp_llist;
+ bool disconnect;
};

#define ISERT_MAX_CQ 64