ixgbe: fix ring reallocation in ethtool

changing ring sizes in ethtool needs to be robust.  If an allocation fails the
driver must continue operation, with the previous settings.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

3 files changed, 56 insertions, 53 deletions

diff --git a/drivers/net/ixgbe/ixgbe.h b/drivers/net/ixgbe/ixgbe.h
index 71ddac6ac4f4..27db64f5c860 100644
--- a/drivers/net/ixgbe/ixgbe.h
+++ b/drivers/net/ixgbe/ixgbe.h
@@ -336,5 +336,9 @@ extern int ixgbe_setup_rx_resources(struct ixgbe_adapter *adapter,
                                     struct ixgbe_ring *rxdr);
 extern int ixgbe_setup_tx_resources(struct ixgbe_adapter *adapter,
                                     struct ixgbe_ring *txdr);
+extern void ixgbe_free_rx_resources(struct ixgbe_adapter *adapter,
+                                    struct ixgbe_ring *rxdr);
+extern void ixgbe_free_tx_resources(struct ixgbe_adapter *adapter,
+                                    struct ixgbe_ring *txdr);
 
 #endif /* _IXGBE_H_ */
diff --git a/drivers/net/ixgbe/ixgbe_ethtool.c b/drivers/net/ixgbe/ixgbe_ethtool.c
index f18e3daaf4f5..928b97cc1700 100644
--- a/drivers/net/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ixgbe/ixgbe_ethtool.c
@@ -654,12 +654,9 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
                                struct ethtool_ringparam *ring)
 {
         struct ixgbe_adapter *adapter = netdev_priv(netdev);
-        struct ixgbe_tx_buffer *old_buf;
-        struct ixgbe_rx_buffer *old_rx_buf;
-        void *old_desc;
+        struct ixgbe_ring *temp_ring;
         int i, err;
-        u32 new_rx_count, new_tx_count, old_size;
-        dma_addr_t old_dma;
+        u32 new_rx_count, new_tx_count;
 
         if ((ring->rx_mini_pending) || (ring->rx_jumbo_pending))
                 return -EINVAL;
@@ -678,6 +675,15 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
                 return 0;
         }
 
+        if (adapter->num_tx_queues > adapter->num_rx_queues)
+                temp_ring = vmalloc(adapter->num_tx_queues *
+                                    sizeof(struct ixgbe_ring));
+        else
+                temp_ring = vmalloc(adapter->num_rx_queues *
+                                    sizeof(struct ixgbe_ring));
+        if (!temp_ring)
+                return -ENOMEM;
+
         while (test_and_set_bit(__IXGBE_RESETTING, &adapter->state))
                 msleep(1);
 
@@ -690,66 +696,59 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
          * to the tx and rx ring structs.
          */
         if (new_tx_count != adapter->tx_ring->count) {
+                memcpy(temp_ring, adapter->tx_ring,
+                       adapter->num_tx_queues * sizeof(struct ixgbe_ring));
+
                 for (i = 0; i < adapter->num_tx_queues; i++) {
-                        /* Save existing descriptor ring */
-                        old_buf = adapter->tx_ring[i].tx_buffer_info;
-                        old_desc = adapter->tx_ring[i].desc;
-                        old_size = adapter->tx_ring[i].size;
-                        old_dma = adapter->tx_ring[i].dma;
-                        /* Try to allocate a new one */
-                        adapter->tx_ring[i].tx_buffer_info = NULL;
-                        adapter->tx_ring[i].desc = NULL;
-                        adapter->tx_ring[i].count = new_tx_count;
-                        err = ixgbe_setup_tx_resources(adapter,
-                                                       &adapter->tx_ring[i]);
+                        temp_ring[i].count = new_tx_count;
+                        err = ixgbe_setup_tx_resources(adapter, &temp_ring[i]);
                         if (err) {
-                                /* Restore the old one so at least
-                                   the adapter still works, even if
-                                   we failed the request */
-                                adapter->tx_ring[i].tx_buffer_info = old_buf;
-                                adapter->tx_ring[i].desc = old_desc;
-                                adapter->tx_ring[i].size = old_size;
-                                adapter->tx_ring[i].dma = old_dma;
+                                while (i) {
+                                        i--;
+                                        ixgbe_free_tx_resources(adapter, &temp_ring[i]);
+                                }
                                 goto err_setup;
                         }
-                        /* Free the old buffer manually */
-                        vfree(old_buf);
-                        pci_free_consistent(adapter->pdev, old_size,
-                                            old_desc, old_dma);
                 }
+
+                for (i = 0; i < adapter->num_tx_queues; i++)
+                        ixgbe_free_tx_resources(adapter, &adapter->tx_ring[i]);
+
+                memcpy(adapter->tx_ring, temp_ring,
+                       adapter->num_tx_queues * sizeof(struct ixgbe_ring));
+
+                adapter->tx_ring_count = new_tx_count;
         }
 
         if (new_rx_count != adapter->rx_ring->count) {
-                for (i = 0; i < adapter->num_rx_queues; i++) {
+                memcpy(temp_ring, adapter->rx_ring,
+                       adapter->num_rx_queues * sizeof(struct ixgbe_ring));
 
-                        old_rx_buf = adapter->rx_ring[i].rx_buffer_info;
-                        old_desc = adapter->rx_ring[i].desc;
-                        old_size = adapter->rx_ring[i].size;
-                        old_dma = adapter->rx_ring[i].dma;
-
-                        adapter->rx_ring[i].rx_buffer_info = NULL;
-                        adapter->rx_ring[i].desc = NULL;
-                        adapter->rx_ring[i].dma = 0;
-                        adapter->rx_ring[i].count = new_rx_count;
-                        err = ixgbe_setup_rx_resources(adapter,
-                                                       &adapter->rx_ring[i]);
+                for (i = 0; i < adapter->num_rx_queues; i++) {
+                        temp_ring[i].count = new_rx_count;
+                        err = ixgbe_setup_rx_resources(adapter, &temp_ring[i]);
                         if (err) {
-                                adapter->rx_ring[i].rx_buffer_info = old_rx_buf;
-                                adapter->rx_ring[i].desc = old_desc;
-                                adapter->rx_ring[i].size = old_size;
-                                adapter->rx_ring[i].dma = old_dma;
+                                while (i) {
+                                        i--;
+                                        ixgbe_free_rx_resources(adapter, &temp_ring[i]);
+                                }
                                 goto err_setup;
                         }
-
-                        vfree(old_rx_buf);
-                        pci_free_consistent(adapter->pdev, old_size, old_desc,
-                                            old_dma);
                 }
+
+                for (i = 0; i < adapter->num_rx_queues; i++)
+                        ixgbe_free_rx_resources(adapter, &adapter->rx_ring[i]);
+
+                memcpy(adapter->rx_ring, temp_ring,
+                       adapter->num_rx_queues * sizeof(struct ixgbe_ring));
+
+                adapter->rx_ring_count = new_rx_count;
         }
 
+        /* success! */
         err = 0;
 err_setup:
-        if (netif_running(adapter->netdev))
+        if (netif_running(netdev))
                 ixgbe_up(adapter);
 
         clear_bit(__IXGBE_RESETTING, &adapter->state);
diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c
index 3b0481a9979e..cde5d5a5a9ab 100644
--- a/drivers/net/ixgbe/ixgbe_main.c
+++ b/drivers/net/ixgbe/ixgbe_main.c
@@ -2731,8 +2731,8 @@ alloc_failed:
  *
  * Free all transmit software resources
  **/
-static void ixgbe_free_tx_resources(struct ixgbe_adapter *adapter,
-                                    struct ixgbe_ring *tx_ring)
+void ixgbe_free_tx_resources(struct ixgbe_adapter *adapter,
+                             struct ixgbe_ring *tx_ring)
 {
         struct pci_dev *pdev = adapter->pdev;
 
@@ -2761,14 +2761,14 @@ static void ixgbe_free_all_tx_resources(struct ixgbe_adapter *adapter)
 }
 
 /**
- * ixgbe_free_rx_resources - Free Rx Resources
+ * ixgbe_ree_rx_resources - Free Rx Resources
  * @adapter: board private structure
  * @rx_ring: ring to clean the resources from
  *
  * Free all receive software resources
  **/
-static void ixgbe_free_rx_resources(struct ixgbe_adapter *adapter,
-                                    struct ixgbe_ring *rx_ring)
+void ixgbe_free_rx_resources(struct ixgbe_adapter *adapter,
+                             struct ixgbe_ring *rx_ring)
 {
         struct pci_dev *pdev = adapter->pdev;