[PATCH] skge: check length from PHY

Cleanup receive buffer allocation and management,
Add more error handling checks from PHY and bump version.
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

2 files changed, 85 insertions, 82 deletions

diff --git a/drivers/net/skge.c b/drivers/net/skge.c
index 62e2ae0eb858..ae1996a3bc5c 100644
--- a/drivers/net/skge.c
+++ b/drivers/net/skge.c
@@ -42,7 +42,7 @@
 #include "skge.h"
 
 #define DRV_NAME                "skge"
-#define DRV_VERSION             "1.0"
+#define DRV_VERSION             "1.1"
 #define PFX                     DRV_NAME " "
 
 #define DEFAULT_TX_RING_SIZE    128
@@ -762,17 +762,6 @@ static int skge_ring_alloc(struct skge_ring *ring, void *vaddr, u64 base)
         return 0;
 }
 
-static struct sk_buff *skge_rx_alloc(struct net_device *dev, unsigned int size)
-{
-        struct sk_buff *skb = dev_alloc_skb(size);
-
-        if (likely(skb)) {
-                skb->dev = dev;
-                skb_reserve(skb, NET_IP_ALIGN);
-        }
-        return skb;
-}
-
 /* Allocate and setup a new buffer for receiving */
 static void skge_rx_setup(struct skge_port *skge, struct skge_element *e,
                           struct sk_buff *skb, unsigned int bufsize)
@@ -845,16 +834,17 @@ static int skge_rx_fill(struct skge_port *skge)
 {
         struct skge_ring *ring = &skge->rx_ring;
         struct skge_element *e;
-        unsigned int bufsize = skge->rx_buf_size;
 
         e = ring->start;
         do {
-                struct sk_buff *skb = skge_rx_alloc(skge->netdev, bufsize);
+                struct sk_buff *skb;
 
+                skb = dev_alloc_skb(skge->rx_buf_size + NET_IP_ALIGN);
                 if (!skb)
                         return -ENOMEM;
 
-                skge_rx_setup(skge, e, skb, bufsize);
+                skb_reserve(skb, NET_IP_ALIGN);
+                skge_rx_setup(skge, e, skb, skge->rx_buf_size);
         } while ( (e = e->next) != ring->start);
 
         ring->to_clean = ring->start;
@@ -2429,6 +2419,14 @@ static void yukon_set_multicast(struct net_device *dev)
         gma_write16(hw, port, GM_RX_CTRL, reg);
 }
 
+static inline u16 phy_length(const struct skge_hw *hw, u32 status)
+{
+        if (hw->chip_id == CHIP_ID_GENESIS)
+                return status >> XMR_FS_LEN_SHIFT;
+        else
+                return status >> GMR_FS_LEN_SHIFT;
+}
+
 static inline int bad_phy_status(const struct skge_hw *hw, u32 status)
 {
         if (hw->chip_id == CHIP_ID_GENESIS)
@@ -2438,80 +2436,99 @@ static inline int bad_phy_status(const struct skge_hw *hw, u32 status)
                         (status & GMR_FS_RX_OK) == 0;
 }
 
-static void skge_rx_error(struct skge_port *skge, int slot,
-                          u32 control, u32 status)
-{
-        if (netif_msg_rx_err(skge))
-                printk(KERN_DEBUG PFX "%s: rx err, slot %d control 0x%x status 0x%x\n",
-                       skge->netdev->name, slot, control, status);
-
-        if ((control & (BMU_EOF|BMU_STF)) != (BMU_STF|BMU_EOF))
-                skge->net_stats.rx_length_errors++;
-        else if (skge->hw->chip_id == CHIP_ID_GENESIS) {
-                if (status & (XMR_FS_RUNT|XMR_FS_LNG_ERR))
-                        skge->net_stats.rx_length_errors++;
-                if (status & XMR_FS_FRA_ERR)
-                        skge->net_stats.rx_frame_errors++;
-                if (status & XMR_FS_FCS_ERR)
-                        skge->net_stats.rx_crc_errors++;
-        } else {
-                if (status & (GMR_FS_LONG_ERR|GMR_FS_UN_SIZE))
-                        skge->net_stats.rx_length_errors++;
-                if (status & GMR_FS_FRAGMENT)
-                        skge->net_stats.rx_frame_errors++;
-                if (status & GMR_FS_CRC_ERR)
-                        skge->net_stats.rx_crc_errors++;
-        }
-}
 
 /* Get receive buffer from descriptor.
  * Handles copy of small buffers and reallocation failures
  */
 static inline struct sk_buff *skge_rx_get(struct skge_port *skge,
                                           struct skge_element *e,
-                                          unsigned int len)
+                                          u32 control, u32 status, u16 csum)
 {
-        struct sk_buff *nskb, *skb;
+        struct sk_buff *skb;
+        u16 len = control & BMU_BBC;
+
+        if (unlikely(netif_msg_rx_status(skge)))
+                printk(KERN_DEBUG PFX "%s: rx slot %td status 0x%x len %d\n",
+                       skge->netdev->name, e - skge->rx_ring.start,
+                       status, len);
+
+        if (len > skge->rx_buf_size)
+                goto error;
+
+        if ((control & (BMU_EOF|BMU_STF)) != (BMU_STF|BMU_EOF))
+                goto error;
+
+        if (bad_phy_status(skge->hw, status))
+                goto error;
+
+        if (phy_length(skge->hw, status) != len)
+                goto error;
 
         if (len < RX_COPY_THRESHOLD) {
-                nskb = skge_rx_alloc(skge->netdev, len + NET_IP_ALIGN);
-                if (unlikely(!nskb))
-                        return NULL;
+                skb = dev_alloc_skb(len + 2);
+                if (!skb)
+                        goto resubmit;
 
+                skb_reserve(skb, 2);
                 pci_dma_sync_single_for_cpu(skge->hw->pdev,
                                             pci_unmap_addr(e, mapaddr),
                                             len, PCI_DMA_FROMDEVICE);
-                memcpy(nskb->data, e->skb->data, len);
+                memcpy(skb->data, e->skb->data, len);
                 pci_dma_sync_single_for_device(skge->hw->pdev,
                                                pci_unmap_addr(e, mapaddr),
                                                len, PCI_DMA_FROMDEVICE);
-
-                if (skge->rx_csum) {
-                        struct skge_rx_desc *rd = e->desc;
-                        nskb->csum = le16_to_cpu(rd->csum2);
-                        nskb->ip_summed = CHECKSUM_HW;
-                }
                 skge_rx_reuse(e, skge->rx_buf_size);
-                return nskb;
         } else {
-                nskb = skge_rx_alloc(skge->netdev, skge->rx_buf_size);
-                if (unlikely(!nskb))
-                        return NULL;
+                struct sk_buff *nskb;
+                nskb = dev_alloc_skb(skge->rx_buf_size + NET_IP_ALIGN);
+                if (!nskb)
+                        goto resubmit;
 
                 pci_unmap_single(skge->hw->pdev,
                                  pci_unmap_addr(e, mapaddr),
                                  pci_unmap_len(e, maplen),
                                  PCI_DMA_FROMDEVICE);
                 skb = e->skb;
-                if (skge->rx_csum) {
-                        struct skge_rx_desc *rd = e->desc;
-                        skb->csum = le16_to_cpu(rd->csum2);
-                        skb->ip_summed = CHECKSUM_HW;
-                }
-
+                prefetch(skb->data);
                 skge_rx_setup(skge, e, nskb, skge->rx_buf_size);
-                return skb;
         }
+
+        skb_put(skb, len);
+        skb->dev = skge->netdev;
+        if (skge->rx_csum) {
+                skb->csum = csum;
+                skb->ip_summed = CHECKSUM_HW;
+        }
+
+        skb->protocol = eth_type_trans(skb, skge->netdev);
+
+        return skb;
+error:
+
+        if (netif_msg_rx_err(skge))
+                printk(KERN_DEBUG PFX "%s: rx err, slot %td control 0x%x status 0x%x\n",
+                       skge->netdev->name, e - skge->rx_ring.start,
+                       control, status);
+
+        if (skge->hw->chip_id == CHIP_ID_GENESIS) {
+                if (status & (XMR_FS_RUNT|XMR_FS_LNG_ERR))
+                        skge->net_stats.rx_length_errors++;
+                if (status & XMR_FS_FRA_ERR)
+                        skge->net_stats.rx_frame_errors++;
+                if (status & XMR_FS_FCS_ERR)
+                        skge->net_stats.rx_crc_errors++;
+        } else {
+                if (status & (GMR_FS_LONG_ERR|GMR_FS_UN_SIZE))
+                        skge->net_stats.rx_length_errors++;
+                if (status & GMR_FS_FRAGMENT)
+                        skge->net_stats.rx_frame_errors++;
+                if (status & GMR_FS_CRC_ERR)
+                        skge->net_stats.rx_crc_errors++;
+        }
+
+resubmit:
+        skge_rx_reuse(e, skge->rx_buf_size);
+        return NULL;
 }
 
 
@@ -2527,32 +2544,16 @@ static int skge_poll(struct net_device *dev, int *budget)
         for (e = ring->to_clean; work_done < to_do; e = e->next) {
                 struct skge_rx_desc *rd = e->desc;
                 struct sk_buff *skb;
-                u32 control, len, status;
+                u32 control;
 
                 rmb();
                 control = rd->control;
                 if (control & BMU_OWN)
                         break;
 
-                len = control & BMU_BBC;
-                status = rd->status;
-
-                if (unlikely((control & (BMU_EOF|BMU_STF)) != (BMU_STF|BMU_EOF)
-                             || bad_phy_status(hw, status))) {
-                        skge_rx_error(skge, e - ring->start, control, status);
-                        skge_rx_reuse(e, skge->rx_buf_size);
-                        continue;
-                }
-
-                if (netif_msg_rx_status(skge))
-                    printk(KERN_DEBUG PFX "%s: rx slot %td status 0x%x len %d\n",
-                           dev->name, e - ring->start, rd->status, len);
-
-                skb = skge_rx_get(skge, e, len);
+                skb = skge_rx_get(skge, e, control, rd->status,
+                                  le16_to_cpu(rd->csum2));
                 if (likely(skb)) {
-                        skb_put(skb, len);
-                        skb->protocol = eth_type_trans(skb, dev);
-
                         dev->last_rx = jiffies;
                         netif_receive_skb(skb);
 
diff --git a/drivers/net/skge.h b/drivers/net/skge.h
index efbf98c675d2..72c175b87a5a 100644
--- a/drivers/net/skge.h
+++ b/drivers/net/skge.h
@@ -953,6 +953,7 @@ enum {
  */
 enum {
         XMR_FS_LEN      = 0x3fff<<18,   /* Bit 31..18:  Rx Frame Length */
+        XMR_FS_LEN_SHIFT = 18,
         XMR_FS_2L_VLAN  = 1<<17, /* Bit 17:     tagged wh 2Lev VLAN ID*/
         XMR_FS_1_VLAN   = 1<<16, /* Bit 16:     tagged wh 1ev VLAN ID*/
         XMR_FS_BC       = 1<<15, /* Bit 15:     Broadcast Frame */
@@ -1868,6 +1869,7 @@ enum {
 /* Receive Frame Status Encoding */
 enum {
         GMR_FS_LEN      = 0xffff<<16, /* Bit 31..16:    Rx Frame Length */
+        GMR_FS_LEN_SHIFT = 16,
         GMR_FS_VLAN     = 1<<13, /* Bit 13:     VLAN Packet */
         GMR_FS_JABBER   = 1<<12, /* Bit 12:     Jabber Packet */
         GMR_FS_UN_SIZE  = 1<<11, /* Bit 11:     Undersize Packet */