igb: remove rx_ps_hdr_len

This patch removes the rx_ps_hdr_len which isn't really needed since we can
now use rx_buffer_len less than 1K to indicate that we are in a packet split
mode.  We also don't need it since we always use a half page for the data
buffers when receiving so we always know the size to map/unmap.

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, 38 insertions, 60 deletions

diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c
index 61ef4c2c4fca..24e502df0889 100644
--- a/drivers/net/igb/igb_main.c
+++ b/drivers/net/igb/igb_main.c
@@ -1862,7 +1862,6 @@ static int __devinit igb_sw_init(struct igb_adapter *adapter)
         adapter->tx_ring_count = IGB_DEFAULT_TXD;
         adapter->rx_ring_count = IGB_DEFAULT_RXD;
         adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE;
-        adapter->rx_ps_hdr_size = 0; /* disable packet split */
         adapter->max_frame_size = netdev->mtu + ETH_HLEN + ETH_FCS_LEN;
         adapter->min_frame_size = ETH_ZLEN + ETH_FCS_LEN;
 
@@ -2254,12 +2253,8 @@ static void igb_setup_rctl(struct igb_adapter *adapter)
          */
         rctl &= ~(E1000_RCTL_SBP | E1000_RCTL_SZ_256);
 
-        /* enable LPE when to prevent packets larger than max_frame_size */
-                rctl |= E1000_RCTL_LPE;
-
-        /* Setup buffer sizes */
-        srrctl = ALIGN(adapter->rx_buffer_len, 1024)
-                 >> E1000_SRRCTL_BSIZEPKT_SHIFT;
+        /* enable LPE to prevent packets larger than max_frame_size */
+        rctl |= E1000_RCTL_LPE;
 
         /* 82575 and greater support packet-split where the protocol
          * header is placed in skb->data and the packet data is
@@ -2270,13 +2265,20 @@ static void igb_setup_rctl(struct igb_adapter *adapter)
          */
         /* allocations using alloc_page take too long for regular MTU
          * so only enable packet split for jumbo frames */
-        if (adapter->netdev->mtu > ETH_DATA_LEN) {
-                adapter->rx_ps_hdr_size = IGB_RXBUFFER_128;
-                srrctl |= adapter->rx_ps_hdr_size <<
-                         E1000_SRRCTL_BSIZEHDRSIZE_SHIFT;
+        if (adapter->rx_buffer_len < IGB_RXBUFFER_1024) {
+                srrctl = ALIGN(adapter->rx_buffer_len, 64) <<
+                         E1000_SRRCTL_BSIZEHDRSIZE_SHIFT;
+#if (PAGE_SIZE / 2) > IGB_RXBUFFER_16384
+                srrctl |= IGB_RXBUFFER_16384 >>
+                          E1000_SRRCTL_BSIZEPKT_SHIFT;
+#else
+                srrctl |= (PAGE_SIZE / 2) >>
+                          E1000_SRRCTL_BSIZEPKT_SHIFT;
+#endif
                 srrctl |= E1000_SRRCTL_DESCTYPE_HDR_SPLIT_ALWAYS;
         } else {
-                adapter->rx_ps_hdr_size = 0;
+                srrctl = ALIGN(adapter->rx_buffer_len, 1024) >>
+                         E1000_SRRCTL_BSIZEPKT_SHIFT;
                 srrctl |= E1000_SRRCTL_DESCTYPE_ADV_ONEBUF;
         }
 
@@ -2647,14 +2649,9 @@ static void igb_clean_rx_ring(struct igb_ring *rx_ring)
         for (i = 0; i < rx_ring->count; i++) {
                 buffer_info = &rx_ring->buffer_info[i];
                 if (buffer_info->dma) {
-                        if (adapter->rx_ps_hdr_size)
-                                pci_unmap_single(pdev, buffer_info->dma,
-                                                 adapter->rx_ps_hdr_size,
-                                                 PCI_DMA_FROMDEVICE);
-                        else
-                                pci_unmap_single(pdev, buffer_info->dma,
-                                                 adapter->rx_buffer_len,
-                                                 PCI_DMA_FROMDEVICE);
+                        pci_unmap_single(pdev, buffer_info->dma,
+                                         adapter->rx_buffer_len,
+                                         PCI_DMA_FROMDEVICE);
                         buffer_info->dma = 0;
                 }
 
@@ -2662,14 +2659,15 @@ static void igb_clean_rx_ring(struct igb_ring *rx_ring)
                         dev_kfree_skb(buffer_info->skb);
                         buffer_info->skb = NULL;
                 }
+                if (buffer_info->page_dma) {
+                        pci_unmap_page(pdev, buffer_info->page_dma,
+                                       PAGE_SIZE / 2,
+                                       PCI_DMA_FROMDEVICE);
+                        buffer_info->page_dma = 0;
+                }
                 if (buffer_info->page) {
-                        if (buffer_info->page_dma)
-                                pci_unmap_page(pdev, buffer_info->page_dma,
-                                               PAGE_SIZE / 2,
-                                               PCI_DMA_FROMDEVICE);
                         put_page(buffer_info->page);
                         buffer_info->page = NULL;
-                        buffer_info->page_dma = 0;
                         buffer_info->page_offset = 0;
                 }
         }
@@ -3792,19 +3790,10 @@ static int igb_change_mtu(struct net_device *netdev, int new_mtu)
 
         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;
-        else
-#if (PAGE_SIZE / 2) > IGB_RXBUFFER_16384
-                adapter->rx_buffer_len = IGB_RXBUFFER_16384;
-#else
-                adapter->rx_buffer_len = PAGE_SIZE / 2;
-#endif
-
-        /* 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))
+        else if (max_frame <= MAXIMUM_ETHERNET_VLAN_SIZE)
                 adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE;
+        else
+                adapter->rx_buffer_len = IGB_RXBUFFER_128;
 
         dev_info(&adapter->pdev->dev, "changing MTU from %d to %d\n",
                  netdev->mtu, new_mtu);
@@ -4864,8 +4853,8 @@ static inline u16 igb_get_hlen(struct igb_adapter *adapter,
          */
         u16 hlen = (le16_to_cpu(rx_desc->wb.lower.lo_dword.hdr_info) &
                    E1000_RXDADV_HDRBUFLEN_MASK) >> E1000_RXDADV_HDRBUFLEN_SHIFT;
-        if (hlen > adapter->rx_ps_hdr_size)
-                hlen = adapter->rx_ps_hdr_size;
+        if (hlen > adapter->rx_buffer_len)
+                hlen = adapter->rx_buffer_len;
         return hlen;
 }
 
@@ -4913,23 +4902,16 @@ static bool igb_clean_rx_irq_adv(struct igb_q_vector *q_vector,
                 cleaned = true;
                 cleaned_count++;
 
-                /* this is the fast path for the non-packet split case */
-                if (!adapter->rx_ps_hdr_size) {
-                        pci_unmap_single(pdev, buffer_info->dma,
-                                         adapter->rx_buffer_len,
-                                         PCI_DMA_FROMDEVICE);
-                        buffer_info->dma = 0;
-                        skb_put(skb, length);
-                        goto send_up;
-                }
-
                 if (buffer_info->dma) {
-                        u16 hlen = igb_get_hlen(adapter, rx_desc);
                         pci_unmap_single(pdev, buffer_info->dma,
-                                         adapter->rx_ps_hdr_size,
+                                         adapter->rx_buffer_len,
                                          PCI_DMA_FROMDEVICE);
                         buffer_info->dma = 0;
-                        skb_put(skb, hlen);
+                        if (adapter->rx_buffer_len >= IGB_RXBUFFER_1024) {
+                                skb_put(skb, length);
+                                goto send_up;
+                        }
+                        skb_put(skb, igb_get_hlen(adapter, rx_desc));
                 }
 
                 if (length) {
@@ -4942,8 +4924,7 @@ static bool igb_clean_rx_irq_adv(struct igb_q_vector *q_vector,
                                                 buffer_info->page_offset,
                                                 length);
 
-                        if ((adapter->rx_buffer_len > (PAGE_SIZE / 2)) ||
-                            (page_count(buffer_info->page) != 1))
+                        if (page_count(buffer_info->page) != 1)
                                 buffer_info->page = NULL;
                         else
                                 get_page(buffer_info->page);
@@ -5070,15 +5051,12 @@ static void igb_alloc_rx_buffers_adv(struct igb_ring *rx_ring,
         i = rx_ring->next_to_use;
         buffer_info = &rx_ring->buffer_info[i];
 
-        if (adapter->rx_ps_hdr_size)
-                bufsz = adapter->rx_ps_hdr_size;
-        else
-                bufsz = adapter->rx_buffer_len;
+        bufsz = adapter->rx_buffer_len;
 
         while (cleaned_count--) {
                 rx_desc = E1000_RX_DESC_ADV(*rx_ring, i);
 
-                if (adapter->rx_ps_hdr_size && !buffer_info->page_dma) {
+                if ((bufsz < IGB_RXBUFFER_1024) && !buffer_info->page_dma) {
                         if (!buffer_info->page) {
                                 buffer_info->page = alloc_page(GFP_ATOMIC);
                                 if (!buffer_info->page) {
@@ -5110,7 +5088,7 @@ static void igb_alloc_rx_buffers_adv(struct igb_ring *rx_ring,
                 }
                 /* Refresh the desc even if buffer_addrs didn't change because
                  * each write-back erases this info. */
-                if (adapter->rx_ps_hdr_size) {
+                if (bufsz < IGB_RXBUFFER_1024) {
                         rx_desc->read.pkt_addr =
                              cpu_to_le64(buffer_info->page_dma);
                         rx_desc->read.hdr_addr = cpu_to_le64(buffer_info->dma);