RDMA/core: Avoid holding lock while initializing fields on stack

In various functions rdma_cm_event is zero initialized on stack using
memset() while holding lock which is not necessary.
Therefore, don't hold the lock while initializing on stack.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 853f73a0499f7599db28b2587a0ff8a2eb4a81bd..fcae854b3ca82ade8927aad15d9d4d8b0c2cc915 100644 (file)
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -1787,7 +1787,7 @@ static int cma_ib_handler(struct ib_cm_id *cm_id,
                          const struct ib_cm_event *ib_event)
 {
        struct rdma_id_private *id_priv = cm_id->context;
-       struct rdma_cm_event event;
+       struct rdma_cm_event event = {};
        int ret = 0;
 
        mutex_lock(&id_priv->handler_mutex);
@@ -1797,7 +1797,6 @@ static int cma_ib_handler(struct ib_cm_id *cm_id,
             id_priv->state != RDMA_CM_DISCONNECT))
                goto out;
 
-       memset(&event, 0, sizeof event);
        switch (ib_event->event) {
        case IB_CM_REQ_ERROR:
        case IB_CM_REP_ERROR:
@@ -2003,7 +2002,7 @@ static int cma_req_handler(struct ib_cm_id *cm_id,
                           const struct ib_cm_event *ib_event)
 {
        struct rdma_id_private *listen_id, *conn_id = NULL;
-       struct rdma_cm_event event;
+       struct rdma_cm_event event = {};
        struct net_device *net_dev;
        u8 offset;
        int ret;
@@ -2023,7 +2022,6 @@ static int cma_req_handler(struct ib_cm_id *cm_id,
                goto err1;
        }
 
-       memset(&event, 0, sizeof event);
        offset = cma_user_data_offset(listen_id);
        event.event = RDMA_CM_EVENT_CONNECT_REQUEST;
        if (ib_event->event == IB_CM_SIDR_REQ_RECEIVED) {
@@ -2132,7 +2130,7 @@ EXPORT_SYMBOL(rdma_read_gids);
 static int cma_iw_handler(struct iw_cm_id *iw_id, struct iw_cm_event *iw_event)
 {
        struct rdma_id_private *id_priv = iw_id->context;
-       struct rdma_cm_event event;
+       struct rdma_cm_event event = {};
        int ret = 0;
        struct sockaddr *laddr = (struct sockaddr *)&iw_event->local_addr;
        struct sockaddr *raddr = (struct sockaddr *)&iw_event->remote_addr;
@@ -2141,7 +2139,6 @@ static int cma_iw_handler(struct iw_cm_id *iw_id, struct iw_cm_event *iw_event)
        if (id_priv->state != RDMA_CM_CONNECT)
                goto out;
 
-       memset(&event, 0, sizeof event);
        switch (iw_event->event) {
        case IW_CM_EVENT_CLOSE:
                event.event = RDMA_CM_EVENT_DISCONNECTED;
@@ -2201,11 +2198,17 @@ static int iw_conn_req_handler(struct iw_cm_id *cm_id,
 {
        struct rdma_cm_id *new_cm_id;
        struct rdma_id_private *listen_id, *conn_id;
-       struct rdma_cm_event event;
+       struct rdma_cm_event event = {};
        int ret = -ECONNABORTED;
        struct sockaddr *laddr = (struct sockaddr *)&iw_event->local_addr;
        struct sockaddr *raddr = (struct sockaddr *)&iw_event->remote_addr;
 
+       event.event = RDMA_CM_EVENT_CONNECT_REQUEST;
+       event.param.conn.private_data = iw_event->private_data;
+       event.param.conn.private_data_len = iw_event->private_data_len;
+       event.param.conn.initiator_depth = iw_event->ird;
+       event.param.conn.responder_resources = iw_event->ord;
+
        listen_id = cm_id->context;
 
        mutex_lock(&listen_id->handler_mutex);
@@ -2247,13 +2250,6 @@ static int iw_conn_req_handler(struct iw_cm_id *cm_id,
        memcpy(cma_src_addr(conn_id), laddr, rdma_addr_size(laddr));
        memcpy(cma_dst_addr(conn_id), raddr, rdma_addr_size(raddr));
 
-       memset(&event, 0, sizeof event);
-       event.event = RDMA_CM_EVENT_CONNECT_REQUEST;
-       event.param.conn.private_data = iw_event->private_data;
-       event.param.conn.private_data_len = iw_event->private_data_len;
-       event.param.conn.initiator_depth = iw_event->ird;
-       event.param.conn.responder_resources = iw_event->ord;
-
        /*
         * Protect against the user destroying conn_id from another thread
         * until we're done accessing it.
@@ -2860,9 +2856,8 @@ static void addr_handler(int status, struct sockaddr *src_addr,
                         struct rdma_dev_addr *dev_addr, void *context)
 {
        struct rdma_id_private *id_priv = context;
-       struct rdma_cm_event event;
+       struct rdma_cm_event event = {};
 
-       memset(&event, 0, sizeof event);
        mutex_lock(&id_priv->handler_mutex);
        if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_QUERY,
                           RDMA_CM_ADDR_RESOLVED))
@@ -3491,7 +3486,7 @@ static int cma_sidr_rep_handler(struct ib_cm_id *cm_id,
                                const struct ib_cm_event *ib_event)
 {
        struct rdma_id_private *id_priv = cm_id->context;
-       struct rdma_cm_event event;
+       struct rdma_cm_event event = {};
        const struct ib_cm_sidr_rep_event_param *rep =
                                &ib_event->param.sidr_rep_rcvd;
        int ret = 0;
@@ -3500,7 +3495,6 @@ static int cma_sidr_rep_handler(struct ib_cm_id *cm_id,
        if (id_priv->state != RDMA_CM_CONNECT)
                goto out;
 
-       memset(&event, 0, sizeof event);
        switch (ib_event->event) {
        case IB_CM_SIDR_REQ_ERROR:
                event.event = RDMA_CM_EVENT_UNREACHABLE;
@@ -3972,7 +3966,7 @@ static int cma_ib_mc_handler(int status, struct ib_sa_multicast *multicast)
 {
        struct rdma_id_private *id_priv;
        struct cma_multicast *mc = multicast->context;
-       struct rdma_cm_event event;
+       struct rdma_cm_event event = {};
        int ret = 0;
 
        id_priv = mc->id_priv;
@@ -3996,7 +3990,6 @@ static int cma_ib_mc_handler(int status, struct ib_sa_multicast *multicast)
        }
        mutex_unlock(&id_priv->qp_mutex);
 
-       memset(&event, 0, sizeof event);
        event.status = status;
        event.param.ud.private_data = mc->context;
        if (!status) {
@@ -4441,7 +4434,7 @@ free_cma_dev:
 
 static int cma_remove_id_dev(struct rdma_id_private *id_priv)
 {
-       struct rdma_cm_event event;
+       struct rdma_cm_event event = {};
        enum rdma_cm_state state;
        int ret = 0;
 
@@ -4457,7 +4450,6 @@ static int cma_remove_id_dev(struct rdma_id_private *id_priv)
        if (!cma_comp(id_priv, RDMA_CM_DEVICE_REMOVAL))
                goto out;
 
-       memset(&event, 0, sizeof event);
        event.event = RDMA_CM_EVENT_DEVICE_REMOVAL;
        ret = id_priv->id.event_handler(&id_priv->id, &event);
 out: