sfc: Allow changing the DMA ring sizes dynamically via ethtool
This requires some reorganisation of channel setup and teardown to
ensure that we can always roll-back a failed change.
Based on work by Steve Hodgson <shodgson@solarflare.com>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/sfc/ethtool.c b/drivers/net/sfc/ethtool.c
index b9291db..7f735d8 100644
--- a/drivers/net/sfc/ethtool.c
+++ b/drivers/net/sfc/ethtool.c
@@ -742,6 +742,42 @@
return 0;
}
+static void efx_ethtool_get_ringparam(struct net_device *net_dev,
+ struct ethtool_ringparam *ring)
+{
+ struct efx_nic *efx = netdev_priv(net_dev);
+
+ ring->rx_max_pending = EFX_MAX_DMAQ_SIZE;
+ ring->tx_max_pending = EFX_MAX_DMAQ_SIZE;
+ ring->rx_mini_max_pending = 0;
+ ring->rx_jumbo_max_pending = 0;
+ ring->rx_pending = efx->rxq_entries;
+ ring->tx_pending = efx->txq_entries;
+ ring->rx_mini_pending = 0;
+ ring->rx_jumbo_pending = 0;
+}
+
+static int efx_ethtool_set_ringparam(struct net_device *net_dev,
+ struct ethtool_ringparam *ring)
+{
+ struct efx_nic *efx = netdev_priv(net_dev);
+
+ if (ring->rx_mini_pending || ring->rx_jumbo_pending ||
+ ring->rx_pending > EFX_MAX_DMAQ_SIZE ||
+ ring->tx_pending > EFX_MAX_DMAQ_SIZE)
+ return -EINVAL;
+
+ if (ring->rx_pending < EFX_MIN_RING_SIZE ||
+ ring->tx_pending < EFX_MIN_RING_SIZE) {
+ netif_err(efx, drv, efx->net_dev,
+ "TX and RX queues cannot be smaller than %ld\n",
+ EFX_MIN_RING_SIZE);
+ return -EINVAL;
+ }
+
+ return efx_realloc_channels(efx, ring->rx_pending, ring->tx_pending);
+}
+
static int efx_ethtool_set_pauseparam(struct net_device *net_dev,
struct ethtool_pauseparam *pause)
{
@@ -972,6 +1008,8 @@
.set_eeprom = efx_ethtool_set_eeprom,
.get_coalesce = efx_ethtool_get_coalesce,
.set_coalesce = efx_ethtool_set_coalesce,
+ .get_ringparam = efx_ethtool_get_ringparam,
+ .set_ringparam = efx_ethtool_set_ringparam,
.get_pauseparam = efx_ethtool_get_pauseparam,
.set_pauseparam = efx_ethtool_set_pauseparam,
.get_rx_csum = efx_ethtool_get_rx_csum,