IB/mlx4: Add multicast group (MCG) paravirtualization for SR-IOV

MCG paravirtualization support includes:
- Creating multicast groups by VFs, and keeping accounting of them
- Leaving multicast groups by VFs
- Updating SM only with real changes in the overall picture of MCGs status
- Creation of MGID=0 groups (let SM choose MGID)

Note that the MCG module maintains its own internal MCG object
reference counts.  The reason for this is that the IB core is used to
track only the multicast groups joins generated by the PF it runs
over.  The PF IB core layer is unaware of slaves, so it cannot be used
to keep track of MCG joins they generate.

Signed-off-by: Oren Duer <oren@mellanox.co.il>
Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 14 insertions, 4 deletions

diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index 45a6cc04036b..b959fe4665dd 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -1628,18 +1628,28 @@ static int __init mlx4_ib_init(void)
         if (!wq)
                 return -ENOMEM;
 
+        err = mlx4_ib_mcg_init();
+        if (err)
+                goto clean_wq;
+
         err = mlx4_register_interface(&mlx4_ib_interface);
-        if (err) {
-                destroy_workqueue(wq);
-                return err;
-        }
+        if (err)
+                goto clean_mcg;
 
         return 0;
+
+clean_mcg:
+        mlx4_ib_mcg_destroy();
+
+clean_wq:
+        destroy_workqueue(wq);
+        return err;
 }
 
 static void __exit mlx4_ib_cleanup(void)
 {
         mlx4_unregister_interface(&mlx4_ib_interface);
+        mlx4_ib_mcg_destroy();
         destroy_workqueue(wq);
 }