[net-next 11/13] net/mlx5e: Vxlan, add sync lock for add/del vxlan port

[Saeed Mahameed]

Vxlan API can and will be called from different mlx5 modules, we should
not count on mlx5e private state lock only, hence we introduce a vxlan
private mutex to sync between add/del vxlan port operations.

Signed-off-by: Saeed Mahameed <sae...@mellanox.com>
Reviewed-by: Or Gerlitz <ogerl...@mellanox.com>
---
 .../net/ethernet/mellanox/mlx5/core/vxlan.c    | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/vxlan.c 
b/drivers/net/ethernet/mellanox/mlx5/core/vxlan.c
index f5353134542d..c126a790234d 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/vxlan.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/vxlan.c
@@ -38,8 +38,9 @@
 
 struct mlx5_vxlan {
        struct mlx5_core_dev            *mdev;
-       rwlock_t                        lock; /* protect vxlan table */
        int                             num_ports;
+       struct mutex                    sync_lock; /* sync add/del port HW 
operations */
+       rwlock_t                        lock; /* sync vxlan table with data 
path access */
        /* max_num_ports is usuallly 4, 16 buckets is more than enough */
        DECLARE_HASHTABLE(htable, 4);
 };
@@ -115,17 +116,18 @@ int mlx5_vxlan_add_port(struct mlx5_vxlan *vxlan, u16 
port)
                return 0;
        }
 
+       mutex_lock(&vxlan->sync_lock);
        if (vxlan->num_ports >= mlx5_vxlan_max_udp_ports(vxlan->mdev)) {
                mlx5_core_info(vxlan->mdev,
                               "UDP port (%d) not offloaded, max number of UDP 
ports (%d) are already offloaded\n",
                               port, mlx5_vxlan_max_udp_ports(vxlan->mdev));
                ret = -ENOSPC;
-               return ret;
+               goto unlock;
        }
 
        ret = mlx5_vxlan_core_add_port_cmd(vxlan->mdev, port);
        if (ret)
-               return ret;
+               goto unlock;
 
        vxlanp = kzalloc(sizeof(*vxlanp), GFP_KERNEL);
        if (!vxlanp) {
@@ -141,10 +143,14 @@ int mlx5_vxlan_add_port(struct mlx5_vxlan *vxlan, u16 
port)
        write_unlock_bh(&vxlan->lock);
 
        vxlan->num_ports++;
+       mutex_unlock(&vxlan->sync_lock);
        return 0;
 
 err_delete_port:
        mlx5_vxlan_core_del_port_cmd(vxlan->mdev, port);
+
+unlock:
+       mutex_unlock(&vxlan->sync_lock);
        return ret;
 }
 
@@ -154,6 +160,8 @@ int mlx5_vxlan_del_port(struct mlx5_vxlan *vxlan, u16 port)
        bool remove = false;
        int ret = 0;
 
+       mutex_lock(&vxlan->sync_lock);
+
        write_lock_bh(&vxlan->lock);
        vxlanp = mlx5_vxlan_lookup_port_locked(vxlan, port);
        if (!vxlanp) {
@@ -174,6 +182,9 @@ int mlx5_vxlan_del_port(struct mlx5_vxlan *vxlan, u16 port)
                kfree(vxlanp);
                vxlan->num_ports--;
        }
+
+       mutex_unlock(&vxlan->sync_lock);
+
        return ret;
 }
 
@@ -189,6 +200,7 @@ struct mlx5_vxlan *mlx5_vxlan_create(struct mlx5_core_dev 
*mdev)
                return ERR_PTR(-ENOMEM);
 
        vxlan->mdev = mdev;
+       mutex_init(&vxlan->sync_lock);
        rwlock_init(&vxlan->lock);
        hash_init(vxlan->htable);
 
-- 
2.17.0