net: cleanups in RX queue allocation

Clean up in RX queue allocation.  In netif_set_real_num_rx_queues
return error on attempt to set zero queues, or requested number is
greater than number of allocated queues.  In netif_alloc_rx_queues,
do BUG_ON if queue_count is zero.

Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 17 insertions, 19 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index f44d29ae5d67..d33adecec44b 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1583,12 +1583,12 @@ int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
 {
         int rc;
 
+        if (rxq < 1 || rxq > dev->num_rx_queues)
+                return -EINVAL;
+
         if (dev->reg_state == NETREG_REGISTERED) {
                 ASSERT_RTNL();
 
-                if (rxq > dev->num_rx_queues)
-                        return -EINVAL;
-
                 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
                                                   rxq);
                 if (rc)
@@ -5013,25 +5013,23 @@ static int netif_alloc_rx_queues(struct net_device *dev)
 {
 #ifdef CONFIG_RPS
         unsigned int i, count = dev->num_rx_queues;
+        struct netdev_rx_queue *rx;
 
-        if (count) {
-                struct netdev_rx_queue *rx;
-
-                rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
-                if (!rx) {
-                        pr_err("netdev: Unable to allocate %u rx queues.\n",
-                               count);
-                        return -ENOMEM;
-                }
-                dev->_rx = rx;
+        BUG_ON(count < 1);
 
-                /*
-                 * Set a pointer to first element in the array which holds the
-                 * reference count.
-                 */
-                for (i = 0; i < count; i++)
-                        rx[i].first = rx;
+        rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
+        if (!rx) {
+                pr_err("netdev: Unable to allocate %u rx queues.\n", count);
+                return -ENOMEM;
         }
+        dev->_rx = rx;
+
+        /*
+         * Set a pointer to first element in the array which holds the
+         * reference count.
+         */
+        for (i = 0; i < count; i++)
+                rx[i].first = rx;
 #endif
         return 0;
 }