Patch "RDMA/cma: Combine cma_ndev_work with cma_work" has been added to the 5.8-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    RDMA/cma: Combine cma_ndev_work with cma_work

to the 5.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     rdma-cma-combine-cma_ndev_work-with-cma_work.patch
and it can be found in the queue-5.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 4398caa79e29a28a14d4d1026f5595a04ca2d191
Author: Jason Gunthorpe <jgg@xxxxxxxxxx>
Date:   Wed Sep 2 11:11:19 2020 +0300

    RDMA/cma: Combine cma_ndev_work with cma_work
    
    [ Upstream commit 7e85bcda8bfe883f4244672ed79f81b7762a1a7e ]
    
    These are the same thing, except that cma_ndev_work doesn't have a state
    transition. Signal no state transition by setting old_state and new_state
    == 0.
    
    In all cases the handler function should not be called once
    rdma_destroy_id() has progressed passed setting the state.
    
    Link: https://lore.kernel.org/r/20200902081122.745412-6-leon@xxxxxxxxxx
    Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx>
    Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 26de0dab60bbb..015b2fe509dca 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -363,12 +363,6 @@ struct cma_work {
 	struct rdma_cm_event	event;
 };
 
-struct cma_ndev_work {
-	struct work_struct	work;
-	struct rdma_id_private	*id;
-	struct rdma_cm_event	event;
-};
-
 struct iboe_mcast_work {
 	struct work_struct	 work;
 	struct rdma_id_private	*id;
@@ -2646,32 +2640,14 @@ static void cma_work_handler(struct work_struct *_work)
 	struct rdma_id_private *id_priv = work->id;
 
 	mutex_lock(&id_priv->handler_mutex);
-	if (!cma_comp_exch(id_priv, work->old_state, work->new_state))
+	if (READ_ONCE(id_priv->state) == RDMA_CM_DESTROYING ||
+	    READ_ONCE(id_priv->state) == RDMA_CM_DEVICE_REMOVAL)
 		goto out_unlock;
-
-	if (cma_cm_event_handler(id_priv, &work->event)) {
-		cma_id_put(id_priv);
-		destroy_id_handler_unlock(id_priv);
-		goto out_free;
+	if (work->old_state != 0 || work->new_state != 0) {
+		if (!cma_comp_exch(id_priv, work->old_state, work->new_state))
+			goto out_unlock;
 	}
 
-out_unlock:
-	mutex_unlock(&id_priv->handler_mutex);
-	cma_id_put(id_priv);
-out_free:
-	kfree(work);
-}
-
-static void cma_ndev_work_handler(struct work_struct *_work)
-{
-	struct cma_ndev_work *work = container_of(_work, struct cma_ndev_work, work);
-	struct rdma_id_private *id_priv = work->id;
-
-	mutex_lock(&id_priv->handler_mutex);
-	if (id_priv->state == RDMA_CM_DESTROYING ||
-	    id_priv->state == RDMA_CM_DEVICE_REMOVAL)
-		goto out_unlock;
-
 	if (cma_cm_event_handler(id_priv, &work->event)) {
 		cma_id_put(id_priv);
 		destroy_id_handler_unlock(id_priv);
@@ -4652,7 +4628,7 @@ EXPORT_SYMBOL(rdma_leave_multicast);
 static int cma_netdev_change(struct net_device *ndev, struct rdma_id_private *id_priv)
 {
 	struct rdma_dev_addr *dev_addr;
-	struct cma_ndev_work *work;
+	struct cma_work *work;
 
 	dev_addr = &id_priv->id.route.addr.dev_addr;
 
@@ -4665,7 +4641,7 @@ static int cma_netdev_change(struct net_device *ndev, struct rdma_id_private *id
 		if (!work)
 			return -ENOMEM;
 
-		INIT_WORK(&work->work, cma_ndev_work_handler);
+		INIT_WORK(&work->work, cma_work_handler);
 		work->id = id_priv;
 		work->event.event = RDMA_CM_EVENT_ADDR_CHANGE;
 		cma_id_get(id_priv);