[PATCH 7/8] 2.6.5-rc2 - sis190 update

[Francois Romieu <romieu@xxxxxxxxxxxxx>]

Replace the giant receive buffer with individually allocated skb.


 drivers/net/sis190.c |   86 +++++++++++++++++++++++++++++++++++----------------
 1 files changed, 60 insertions(+), 26 deletions(-)

diff -puN drivers/net/sis190.c~sis190-dma-api-rx-buffers-30 drivers/net/sis190.c
--- linux-2.6.5-rc2/drivers/net/sis190.c~sis190-dma-api-rx-buffers-30   
2004-03-27 02:37:47.000000000 +0100
+++ linux-2.6.5-rc2-fr/drivers/net/sis190.c     2004-03-27 02:37:47.000000000 
+0100
@@ -290,6 +290,9 @@ enum _DescStatusBit {
        ENDbit                  = 0x80000000,
 };
 
+/* FIXME: datasheet, anyone ? */
+#define RsvdMask               0x00000000
+
 struct TxDesc {
        u32 PSize;
        u32 status;
@@ -318,9 +321,8 @@ struct sis190_private {
        dma_addr_t rx_dma;
        struct TxDesc *TxDescArray;     /* Index of 256-alignment Tx Descriptor 
buffer */
        struct RxDesc *RxDescArray;     /* Index of 256-alignment Rx Descriptor 
buffer */
-       unsigned char *RxBufferRings;   /* Index of Rx Buffer  */
-       unsigned char *RxBufferRing[NUM_RX_DESC];       /* Index of Rx Buffer 
array */
-       struct sk_buff *Tx_skbuff[NUM_TX_DESC]; /* Index of Transmit data 
buffer */
+       struct sk_buff *Rx_skbuff[NUM_TX_DESC]; /* Rx data buffer */
+       struct sk_buff *Tx_skbuff[NUM_TX_DESC]; /* Tx data buffer */
 };
 
 MODULE_AUTHOR("K.M. Liu <kmliu@xxxxxxx>");
@@ -812,6 +814,22 @@ static inline void sis190_mark_as_last_d
        desc->buf_Len |= cpu_to_le32(ENDbit);
 }
 
+static inline void sis190_make_unusable_by_asic(struct RxDesc *desc)
+{
+       desc->buf_addr = 0xdeadbeef;
+       desc->status &= ~cpu_to_le32(OWNbit | RsvdMask);
+}
+
+static void sis190_free_rx_skb(struct pci_dev *pdev, struct sk_buff **sk_buff,
+                              struct RxDesc *desc)
+{
+       pci_unmap_single(pdev, le32_to_cpu(desc->buf_addr), RX_BUF_SIZE,
+                        PCI_DMA_FROMDEVICE);
+       dev_kfree_skb(*sk_buff);
+       *sk_buff = NULL;
+       sis190_make_unusable_by_asic(desc);
+}
+
 static inline void sis190_give_to_asic(struct RxDesc *desc, dma_addr_t mapping)
 {
        desc->buf_addr = cpu_to_le32(mapping);
@@ -819,19 +837,47 @@ static inline void sis190_give_to_asic(s
 }
 
 static int sis190_alloc_rx_skb(struct pci_dev *pdev, struct net_device *dev,
-                              char *tail, struct RxDesc *desc)
+                              struct sk_buff **sk_buff, struct RxDesc *desc)
 {
+       struct sk_buff *skb;
        dma_addr_t mapping;
        int ret = 0;
 
-       mapping = pci_map_single(pdev, tail, RX_BUF_SIZE, PCI_DMA_FROMDEVICE);
+       skb = dev_alloc_skb(RX_BUF_SIZE + 2);
+       if (!skb)
+               goto err_out;
+
+       skb->dev = dev;
+       skb_reserve(skb, 2);
+       *sk_buff = skb;
+
+       mapping = pci_map_single(pdev, skb->tail, RX_BUF_SIZE,
+                                PCI_DMA_FROMDEVICE);
 
        desc->PSize = 0x0;
        desc->buf_Len |= cpu_to_le32(RX_BUF_SIZE);
 
        sis190_give_to_asic(desc, mapping);
 
+out:
        return ret;
+
+err_out:
+       ret = -ENOMEM;
+       sis190_make_unusable_by_asic(desc);
+       goto out;
+}
+
+static void sis190_rx_clear(struct sis190_private *tp)
+{
+       int i;
+
+       for (i = 0; i < NUM_RX_DESC; i++) {
+               if (tp->Rx_skbuff[i]) {
+                       sis190_free_rx_skb(tp->pci_dev, tp->Rx_skbuff + i,
+                                          tp->RxDescArray + i);
+               }
+       }
 }
 
 static u32 sis190_rx_fill(struct sis190_private *tp, struct net_device *dev,
@@ -842,8 +888,10 @@ static u32 sis190_rx_fill(struct sis190_
        for (cur = start; end - cur > 0; cur++) {
                int ret, i = cur % NUM_RX_DESC;
 
-               ret = sis190_alloc_rx_skb(tp->pci_dev, dev,
-                                         tp->RxBufferRings + i * RX_BUF_SIZE,
+               if (tp->Rx_skbuff[i])
+                       continue;
+
+               ret = sis190_alloc_rx_skb(tp->pci_dev, dev, tp->Rx_skbuff + i,
                                          tp->RxDescArray + i);
                if (ret < 0)
                        break;
@@ -861,24 +909,17 @@ static int SiS190_init_ring(struct net_d
        memset(tp->RxDescArray, 0x0, NUM_RX_DESC * sizeof (struct RxDesc));
 
        memset(tp->Tx_skbuff, 0x0, NUM_TX_DESC * sizeof(struct sk_buff *));
-
-       tp->RxBufferRings = kmalloc(RX_BUF_SIZE * NUM_RX_DESC, GFP_KERNEL);
-       if (tp->RxBufferRings == NULL) {
-               printk(KERN_INFO "%s: allocate RxBufferRing failed\n",
-                       dev->name);
-               goto err_out;
-       }
+       memset(tp->Rx_skbuff, 0x0, NUM_RX_DESC * sizeof(struct sk_buff *));
 
        if (sis190_rx_fill(tp, dev, 0, NUM_RX_DESC) != NUM_RX_DESC)
-               goto err_out_free;
+               goto err_out;
 
        sis190_mark_as_last_descriptor(tp->RxDescArray + NUM_RX_DESC - 1);
 
        return 0;
 
-err_out_free:
-       kfree(tp->RxBufferRings);
 err_out:
+       sis190_rx_clear(tp);
        return -ENOMEM;
 }
 
@@ -1065,7 +1106,7 @@ SiS190_rx_interrupt(struct net_device *d
                                pci_dma_sync_single_for_cpu(tp->pci_dev,
                                        le32_to_cpu(desc->buf_addr),
                                        RX_BUF_SIZE, PCI_DMA_FROMDEVICE);
-                               eth_copy_and_sum(skb, tp->RxBufferRing[cur_rx],
+                               eth_copy_and_sum(skb, 
tp->Rx_skbuff[cur_rx]->tail,
                                                 pkt_size, 0);
                                pci_dma_sync_single_for_device(tp->pci_dev,
                                        le32_to_cpu(desc->buf_addr),
@@ -1150,7 +1191,6 @@ SiS190_close(struct net_device *dev)
 {
        struct sis190_private *tp = dev->priv;
        void *ioaddr = tp->mmio_addr;
-       int i;
 
        netif_stop_queue(dev);
 
@@ -1173,19 +1213,13 @@ SiS190_close(struct net_device *dev)
        free_irq(dev->irq, dev);
 
        SiS190_tx_clear(tp);
+       sis190_rx_clear(tp);
        pci_free_consistent(tp->pci_dev, TX_DESC_TOTAL_SIZE, tp->TxDescArray,
                tp->tx_dma);
        pci_free_consistent(tp->pci_dev, RX_DESC_TOTAL_SIZE, tp->RxDescArray,
                tp->rx_dma);
        tp->TxDescArray = NULL;
-       for (i = 0; i < NUM_RX_DESC; i++) {
-               pci_unmap_single(tp->pci_dev,
-                       le32_to_cpu(tp->RxDescArray[i].buf_addr), RX_BUF_SIZE,
-                       PCI_DMA_FROMDEVICE);
-               tp->RxBufferRing[i] = NULL;
-       }
        tp->RxDescArray = NULL;
-       kfree(tp->RxBufferRings);
 
        return 0;
 }

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