veth: factor out initialization helper

Extract in simpler helpers the code to enable and disable a
range of xdp/napi instance, with the common property that
"disable" helpers can't fail.

Will be used by the next patch. No functional change intended.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index 4b3e261..9eb8c10 100644 (file)
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -926,12 +926,12 @@ static int veth_poll(struct napi_struct *napi, int budget)
        return done;
 }
 
-static int __veth_napi_enable(struct net_device *dev)
+static int __veth_napi_enable_range(struct net_device *dev, int start, int end)
 {
        struct veth_priv *priv = netdev_priv(dev);
        int err, i;
 
-       for (i = 0; i < dev->real_num_rx_queues; i++) {
+       for (i = start; i < end; i++) {
                struct veth_rq *rq = &priv->rq[i];
 
                err = ptr_ring_init(&rq->xdp_ring, VETH_RING_SIZE, GFP_KERNEL);
@@ -939,7 +939,7 @@ static int __veth_napi_enable(struct net_device *dev)
                        goto err_xdp_ring;
        }
 
-       for (i = 0; i < dev->real_num_rx_queues; i++) {
+       for (i = start; i < end; i++) {
                struct veth_rq *rq = &priv->rq[i];
 
                napi_enable(&rq->xdp_napi);
@@ -947,19 +947,25 @@ static int __veth_napi_enable(struct net_device *dev)
        }
 
        return 0;
+
 err_xdp_ring:
-       for (i--; i >= 0; i--)
+       for (i--; i >= start; i--)
                ptr_ring_cleanup(&priv->rq[i].xdp_ring, veth_ptr_free);
 
        return err;
 }
 
-static void veth_napi_del(struct net_device *dev)
+static int __veth_napi_enable(struct net_device *dev)
+{
+       return __veth_napi_enable_range(dev, 0, dev->real_num_rx_queues);
+}
+
+static void veth_napi_del_range(struct net_device *dev, int start, int end)
 {
        struct veth_priv *priv = netdev_priv(dev);
        int i;
 
-       for (i = 0; i < dev->real_num_rx_queues; i++) {
+       for (i = start; i < end; i++) {
                struct veth_rq *rq = &priv->rq[i];
 
                rcu_assign_pointer(priv->rq[i].napi, NULL);
@@ -968,7 +974,7 @@ static void veth_napi_del(struct net_device *dev)
        }
        synchronize_net();
 
-       for (i = 0; i < dev->real_num_rx_queues; i++) {
+       for (i = start; i < end; i++) {
                struct veth_rq *rq = &priv->rq[i];
 
                rq->rx_notify_masked = false;
@@ -976,41 +982,90 @@ static void veth_napi_del(struct net_device *dev)
        }
 }
 
+static void veth_napi_del(struct net_device *dev)
+{
+       veth_napi_del_range(dev, 0, dev->real_num_rx_queues);
+}
+
 static bool veth_gro_requested(const struct net_device *dev)
 {
        return !!(dev->wanted_features & NETIF_F_GRO);
 }
 
-static int veth_enable_xdp(struct net_device *dev)
+static int veth_enable_xdp_range(struct net_device *dev, int start, int end,
+                                bool napi_already_on)
 {
-       bool napi_already_on = veth_gro_requested(dev) && (dev->flags & IFF_UP);
        struct veth_priv *priv = netdev_priv(dev);
        int err, i;
 
-       if (!xdp_rxq_info_is_reg(&priv->rq[0].xdp_rxq)) {
-               for (i = 0; i < dev->real_num_rx_queues; i++) {
-                       struct veth_rq *rq = &priv->rq[i];
+       for (i = start; i < end; i++) {
+               struct veth_rq *rq = &priv->rq[i];
 
-                       if (!napi_already_on)
-                               netif_napi_add(dev, &rq->xdp_napi, veth_poll, NAPI_POLL_WEIGHT);
-                       err = xdp_rxq_info_reg(&rq->xdp_rxq, dev, i, rq->xdp_napi.napi_id);
-                       if (err < 0)
-                               goto err_rxq_reg;
+               if (!napi_already_on)
+                       netif_napi_add(dev, &rq->xdp_napi, veth_poll, NAPI_POLL_WEIGHT);
+               err = xdp_rxq_info_reg(&rq->xdp_rxq, dev, i, rq->xdp_napi.napi_id);
+               if (err < 0)
+                       goto err_rxq_reg;
 
-                       err = xdp_rxq_info_reg_mem_model(&rq->xdp_rxq,
-                                                        MEM_TYPE_PAGE_SHARED,
-                                                        NULL);
-                       if (err < 0)
-                               goto err_reg_mem;
+               err = xdp_rxq_info_reg_mem_model(&rq->xdp_rxq,
+                                                MEM_TYPE_PAGE_SHARED,
+                                                NULL);
+               if (err < 0)
+                       goto err_reg_mem;
 
-                       /* Save original mem info as it can be overwritten */
-                       rq->xdp_mem = rq->xdp_rxq.mem;
-               }
+               /* Save original mem info as it can be overwritten */
+               rq->xdp_mem = rq->xdp_rxq.mem;
+       }
+       return 0;
+
+err_reg_mem:
+       xdp_rxq_info_unreg(&priv->rq[i].xdp_rxq);
+err_rxq_reg:
+       for (i--; i >= start; i--) {
+               struct veth_rq *rq = &priv->rq[i];
+
+               xdp_rxq_info_unreg(&rq->xdp_rxq);
+               if (!napi_already_on)
+                       netif_napi_del(&rq->xdp_napi);
+       }
+
+       return err;
+}
+
+static void veth_disable_xdp_range(struct net_device *dev, int start, int end,
+                                  bool delete_napi)
+{
+       struct veth_priv *priv = netdev_priv(dev);
+       int i;
+
+       for (i = start; i < end; i++) {
+               struct veth_rq *rq = &priv->rq[i];
+
+               rq->xdp_rxq.mem = rq->xdp_mem;
+               xdp_rxq_info_unreg(&rq->xdp_rxq);
+
+               if (delete_napi)
+                       netif_napi_del(&rq->xdp_napi);
+       }
+}
+
+static int veth_enable_xdp(struct net_device *dev)
+{
+       bool napi_already_on = veth_gro_requested(dev) && (dev->flags & IFF_UP);
+       struct veth_priv *priv = netdev_priv(dev);
+       int err, i;
+
+       if (!xdp_rxq_info_is_reg(&priv->rq[0].xdp_rxq)) {
+               err = veth_enable_xdp_range(dev, 0, dev->real_num_rx_queues, napi_already_on);
+               if (err)
+                       return err;
 
                if (!napi_already_on) {
                        err = __veth_napi_enable(dev);
-                       if (err)
-                               goto err_rxq_reg;
+                       if (err) {
+                               veth_disable_xdp_range(dev, 0, dev->real_num_rx_queues, true);
+                               return err;
+                       }
 
                        if (!veth_gro_requested(dev)) {
                                /* user-space did not require GRO, but adding XDP
@@ -1028,18 +1083,6 @@ static int veth_enable_xdp(struct net_device *dev)
        }
 
        return 0;
-err_reg_mem:
-       xdp_rxq_info_unreg(&priv->rq[i].xdp_rxq);
-err_rxq_reg:
-       for (i--; i >= 0; i--) {
-               struct veth_rq *rq = &priv->rq[i];
-
-               xdp_rxq_info_unreg(&rq->xdp_rxq);
-               if (!napi_already_on)
-                       netif_napi_del(&rq->xdp_napi);
-       }
-
-       return err;
 }
 
 static void veth_disable_xdp(struct net_device *dev)
@@ -1062,28 +1105,23 @@ static void veth_disable_xdp(struct net_device *dev)
                }
        }
 
-       for (i = 0; i < dev->real_num_rx_queues; i++) {
-               struct veth_rq *rq = &priv->rq[i];
-
-               rq->xdp_rxq.mem = rq->xdp_mem;
-               xdp_rxq_info_unreg(&rq->xdp_rxq);
-       }
+       veth_disable_xdp_range(dev, 0, dev->real_num_rx_queues, false);
 }
 
-static int veth_napi_enable(struct net_device *dev)
+static int veth_napi_enable_range(struct net_device *dev, int start, int end)
 {
        struct veth_priv *priv = netdev_priv(dev);
        int err, i;
 
-       for (i = 0; i < dev->real_num_rx_queues; i++) {
+       for (i = start; i < end; i++) {
                struct veth_rq *rq = &priv->rq[i];
 
                netif_napi_add(dev, &rq->xdp_napi, veth_poll, NAPI_POLL_WEIGHT);
        }
 
-       err = __veth_napi_enable(dev);
+       err = __veth_napi_enable_range(dev, start, end);
        if (err) {
-               for (i = 0; i < dev->real_num_rx_queues; i++) {
+               for (i = start; i < end; i++) {
                        struct veth_rq *rq = &priv->rq[i];
 
                        netif_napi_del(&rq->xdp_napi);
@@ -1093,6 +1131,11 @@ static int veth_napi_enable(struct net_device *dev)
        return err;
 }
 
+static int veth_napi_enable(struct net_device *dev)
+{
+       return veth_napi_enable_range(dev, 0, dev->real_num_rx_queues);
+}
+
 static int veth_open(struct net_device *dev)
 {
        struct veth_priv *priv = netdev_priv(dev);