igb: increase minimum rx buffer size to 1K

This update increases the minimum rx buffer size to 1K.  The reason for this
change is to support SR-IOV and avoid any conflicts with the rings being able
to set their own MTU sizes.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 22 deletions

diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c
index e1d1c0c984b0..6146f5db9871 100644
--- a/drivers/net/igb/igb_main.c
+++ b/drivers/net/igb/igb_main.c
@@ -2233,18 +2233,8 @@ static void igb_setup_rctl(struct igb_adapter *adapter)
                 rctl |= E1000_RCTL_LPE;
 
         /* Setup buffer sizes */
-        switch (adapter->rx_buffer_len) {
-        case IGB_RXBUFFER_256:
-                rctl |= E1000_RCTL_SZ_256;
-                break;
-        case IGB_RXBUFFER_512:
-                rctl |= E1000_RCTL_SZ_512;
-                break;
-        default:
-                srrctl = ALIGN(adapter->rx_buffer_len, 1024)
-                         >> E1000_SRRCTL_BSIZEPKT_SHIFT;
-                break;
-        }
+        srrctl = ALIGN(adapter->rx_buffer_len, 1024)
+                 >> E1000_SRRCTL_BSIZEPKT_SHIFT;
 
         /* 82575 and greater support packet-split where the protocol
          * header is placed in skb->data and the packet data is
@@ -3755,11 +3745,7 @@ static int igb_change_mtu(struct net_device *netdev, int new_mtu)
          * i.e. RXBUFFER_2048 --> size-4096 slab
          */
 
-        if (max_frame <= IGB_RXBUFFER_256)
-                adapter->rx_buffer_len = IGB_RXBUFFER_256;
-        else if (max_frame <= IGB_RXBUFFER_512)
-                adapter->rx_buffer_len = IGB_RXBUFFER_512;
-        else if (max_frame <= IGB_RXBUFFER_1024)
+        if (max_frame <= IGB_RXBUFFER_1024)
                 adapter->rx_buffer_len = IGB_RXBUFFER_1024;
         else if (max_frame <= IGB_RXBUFFER_2048)
                 adapter->rx_buffer_len = IGB_RXBUFFER_2048;
@@ -3770,11 +3756,6 @@ static int igb_change_mtu(struct net_device *netdev, int new_mtu)
                 adapter->rx_buffer_len = PAGE_SIZE / 2;
 #endif
 
-        /* if sr-iov is enabled we need to force buffer size to 1K or larger */
-        if (adapter->vfs_allocated_count &&
-            (adapter->rx_buffer_len < IGB_RXBUFFER_1024))
-                adapter->rx_buffer_len = IGB_RXBUFFER_1024;
-
         /* adjust allocation if LPE protects us, and we aren't using SBP */
         if ((max_frame == ETH_FRAME_LEN + ETH_FCS_LEN) ||
              (max_frame == MAXIMUM_ETHERNET_VLAN_SIZE))