e1000e: re-factor ethtool get/set ring parameter

Make it more like how igb does it, with some additional error checking.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/e1000e/ethtool.c b/drivers/net/ethernet/intel/e1000e/ethtool.c
index 01c73ae..ffb6c14 100644 (file)
--- a/drivers/net/ethernet/intel/e1000e/ethtool.c
+++ b/drivers/net/ethernet/intel/e1000e/ethtool.c
@@ -605,94 +605,112 @@ static void e1000_get_ringparam(struct net_device *netdev,
                                struct ethtool_ringparam *ring)
 {
        struct e1000_adapter *adapter = netdev_priv(netdev);
-       struct e1000_ring *tx_ring = adapter->tx_ring;
-       struct e1000_ring *rx_ring = adapter->rx_ring;
 
        ring->rx_max_pending = E1000_MAX_RXD;
        ring->tx_max_pending = E1000_MAX_TXD;
-       ring->rx_pending = rx_ring->count;
-       ring->tx_pending = tx_ring->count;
+       ring->rx_pending = adapter->rx_ring_count;
+       ring->tx_pending = adapter->tx_ring_count;
 }
 
 static int e1000_set_ringparam(struct net_device *netdev,
                               struct ethtool_ringparam *ring)
 {
        struct e1000_adapter *adapter = netdev_priv(netdev);
-       struct e1000_ring *tx_ring, *tx_old;
-       struct e1000_ring *rx_ring, *rx_old;
-       int err;
+       struct e1000_ring *temp_tx = NULL, *temp_rx = NULL;
+       int err = 0, size = sizeof(struct e1000_ring);
+       bool set_tx = false, set_rx = false;
+       u16 new_rx_count, new_tx_count;
 
        if ((ring->rx_mini_pending) || (ring->rx_jumbo_pending))
                return -EINVAL;
 
-       while (test_and_set_bit(__E1000_RESETTING, &adapter->state))
-               usleep_range(1000, 2000);
+       new_rx_count = clamp_t(u32, ring->rx_pending, E1000_MIN_RXD,
+                              E1000_MAX_RXD);
+       new_rx_count = ALIGN(new_rx_count, REQ_RX_DESCRIPTOR_MULTIPLE);
 
-       if (netif_running(adapter->netdev))
-               e1000e_down(adapter);
+       new_tx_count = clamp_t(u32, ring->tx_pending, E1000_MIN_TXD,
+                              E1000_MAX_TXD);
+       new_tx_count = ALIGN(new_tx_count, REQ_TX_DESCRIPTOR_MULTIPLE);
 
-       tx_old = adapter->tx_ring;
-       rx_old = adapter->rx_ring;
+       if ((new_tx_count == adapter->tx_ring_count) &&
+           (new_rx_count == adapter->rx_ring_count))
+               /* nothing to do */
+               return 0;
 
-       err = -ENOMEM;
-       tx_ring = kmemdup(tx_old, sizeof(struct e1000_ring), GFP_KERNEL);
-       if (!tx_ring)
-               goto err_alloc_tx;
+       while (test_and_set_bit(__E1000_RESETTING, &adapter->state))
+               usleep_range(1000, 2000);
 
-       rx_ring = kmemdup(rx_old, sizeof(struct e1000_ring), GFP_KERNEL);
-       if (!rx_ring)
-               goto err_alloc_rx;
+       if (!netif_running(adapter->netdev)) {
+               /* Set counts now and allocate resources during open() */
+               adapter->tx_ring->count = new_tx_count;
+               adapter->rx_ring->count = new_rx_count;
+               adapter->tx_ring_count = new_tx_count;
+               adapter->rx_ring_count = new_rx_count;
+               goto clear_reset;
+       }
 
-       adapter->tx_ring = tx_ring;
-       adapter->rx_ring = rx_ring;
+       set_tx = (new_tx_count != adapter->tx_ring_count);
+       set_rx = (new_rx_count != adapter->rx_ring_count);
 
-       rx_ring->count = max(ring->rx_pending, (u32)E1000_MIN_RXD);
-       rx_ring->count = min(rx_ring->count, (u32)(E1000_MAX_RXD));
-       rx_ring->count = ALIGN(rx_ring->count, REQ_RX_DESCRIPTOR_MULTIPLE);
+       /* Allocate temporary storage for ring updates */
+       if (set_tx) {
+               temp_tx = vmalloc(size);
+               if (!temp_tx) {
+                       err = -ENOMEM;
+                       goto free_temp;
+               }
+       }
+       if (set_rx) {
+               temp_rx = vmalloc(size);
+               if (!temp_rx) {
+                       err = -ENOMEM;
+                       goto free_temp;
+               }
+       }
 
-       tx_ring->count = max(ring->tx_pending, (u32)E1000_MIN_TXD);
-       tx_ring->count = min(tx_ring->count, (u32)(E1000_MAX_TXD));
-       tx_ring->count = ALIGN(tx_ring->count, REQ_TX_DESCRIPTOR_MULTIPLE);
+       e1000e_down(adapter);
 
-       if (netif_running(adapter->netdev)) {
-               /* Try to get new resources before deleting old */
-               err = e1000e_setup_rx_resources(rx_ring);
+       /*
+        * We can't just free everything and then setup again, because the
+        * ISRs in MSI-X mode get passed pointers to the Tx and Rx ring
+        * structs.  First, attempt to allocate new resources...
+        */
+       if (set_tx) {
+               memcpy(temp_tx, adapter->tx_ring, size);
+               temp_tx->count = new_tx_count;
+               err = e1000e_setup_tx_resources(temp_tx);
                if (err)
-                       goto err_setup_rx;
-               err = e1000e_setup_tx_resources(tx_ring);
+                       goto err_setup;
+       }
+       if (set_rx) {
+               memcpy(temp_rx, adapter->rx_ring, size);
+               temp_rx->count = new_rx_count;
+               err = e1000e_setup_rx_resources(temp_rx);
                if (err)
-                       goto err_setup_tx;
+                       goto err_setup_rx;
+       }
 
-               /*
-                * restore the old in order to free it,
-                * then add in the new
-                */
-               adapter->rx_ring = rx_old;
-               adapter->tx_ring = tx_old;
-               e1000e_free_rx_resources(adapter->rx_ring);
+       /* ...then free the old resources and copy back any new ring data */
+       if (set_tx) {
                e1000e_free_tx_resources(adapter->tx_ring);
-               kfree(tx_old);
-               kfree(rx_old);
-               adapter->rx_ring = rx_ring;
-               adapter->tx_ring = tx_ring;
-               err = e1000e_up(adapter);
-               if (err)
-                       goto err_setup;
+               memcpy(adapter->tx_ring, temp_tx, size);
+               adapter->tx_ring_count = new_tx_count;
+       }
+       if (set_rx) {
+               e1000e_free_rx_resources(adapter->rx_ring);
+               memcpy(adapter->rx_ring, temp_rx, size);
+               adapter->rx_ring_count = new_rx_count;
        }
 
-       clear_bit(__E1000_RESETTING, &adapter->state);
-       return 0;
-err_setup_tx:
-       e1000e_free_rx_resources(rx_ring);
 err_setup_rx:
-       adapter->rx_ring = rx_old;
-       adapter->tx_ring = tx_old;
-       kfree(rx_ring);
-err_alloc_rx:
-       kfree(tx_ring);
-err_alloc_tx:
-       e1000e_up(adapter);
+       if (err && set_tx)
+               e1000e_free_tx_resources(temp_tx);
 err_setup:
+       e1000e_up(adapter);
+free_temp:
+       vfree(temp_tx);
+       vfree(temp_rx);
+clear_reset:
        clear_bit(__E1000_RESETTING, &adapter->state);
        return err;
 }