From fa45459e5e4507402350f1cdaf44b7455602770c Mon Sep 17 00:00:00 2001 From: Ayaz Abdulla Date: Thu, 5 Jan 2006 22:45:45 -0800 Subject: [PATCH] [PATCH] forcedeth: TSO fix for large buffers This contains a bug fix for large buffers. Originally, if a tx buffer to be sent was larger then the maximum size of the tx descriptor, it would overwrite other control bits. In this patch, the buffer is split over multiple descriptors. Also, the fragments are now setup in forward order. Signed-off-by: Ayaz Abdulla Signed-off-by: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Jeff Garzik --- drivers/net/forcedeth.c | 164 ++++++++++++++++++++++++---------------- 1 file changed, 100 insertions(+), 64 deletions(-) diff --git a/drivers/net/forcedeth.c b/drivers/net/forcedeth.c index c39344adec..3682ec61e8 100644 --- a/drivers/net/forcedeth.c +++ b/drivers/net/forcedeth.c @@ -101,6 +101,7 @@ * 0.46: 20 Oct 2005: Add irq optimization modes. * 0.47: 26 Oct 2005: Add phyaddr 0 in phy scan. * 0.48: 24 Dec 2005: Disable TSO, bugfix for pci_map_single + * 0.49: 10 Dec 2005: Fix tso for large buffers. * * Known bugs: * We suspect that on some hardware no TX done interrupts are generated. @@ -112,7 +113,7 @@ * DEV_NEED_TIMERIRQ will not harm you on sane hardware, only generating a few * superfluous timer interrupts from the nic. */ -#define FORCEDETH_VERSION "0.48" +#define FORCEDETH_VERSION "0.49" #define DRV_NAME "forcedeth" #include @@ -349,6 +350,8 @@ typedef union _ring_type { #define NV_TX2_VALID (1<<31) #define NV_TX2_TSO (1<<28) #define NV_TX2_TSO_SHIFT 14 +#define NV_TX2_TSO_MAX_SHIFT 14 +#define NV_TX2_TSO_MAX_SIZE (1<tx_ring.ex[i].FlagLen = 0; np->tx_skbuff[i] = NULL; + np->tx_dma[i] = 0; } } @@ -945,30 +950,27 @@ static int nv_init_ring(struct net_device *dev) return nv_alloc_rx(dev); } -static void nv_release_txskb(struct net_device *dev, unsigned int skbnr) +static int nv_release_txskb(struct net_device *dev, unsigned int skbnr) { struct fe_priv *np = netdev_priv(dev); - struct sk_buff *skb = np->tx_skbuff[skbnr]; - unsigned int j, entry, fragments; - - dprintk(KERN_INFO "%s: nv_release_txskb for skbnr %d, skb %p\n", - dev->name, skbnr, np->tx_skbuff[skbnr]); - - entry = skbnr; - if ((fragments = skb_shinfo(skb)->nr_frags) != 0) { - for (j = fragments; j >= 1; j--) { - skb_frag_t *frag = &skb_shinfo(skb)->frags[j-1]; - pci_unmap_page(np->pci_dev, np->tx_dma[entry], - frag->size, - PCI_DMA_TODEVICE); - entry = (entry - 1) % TX_RING; - } + + dprintk(KERN_INFO "%s: nv_release_txskb for skbnr %d\n", + dev->name, skbnr); + + if (np->tx_dma[skbnr]) { + pci_unmap_page(np->pci_dev, np->tx_dma[skbnr], + np->tx_dma_len[skbnr], + PCI_DMA_TODEVICE); + np->tx_dma[skbnr] = 0; + } + + if (np->tx_skbuff[skbnr]) { + dev_kfree_skb_irq(np->tx_skbuff[skbnr]); + np->tx_skbuff[skbnr] = NULL; + return 1; + } else { + return 0; } - pci_unmap_single(np->pci_dev, np->tx_dma[entry], - skb->len - skb->data_len, - PCI_DMA_TODEVICE); - dev_kfree_skb_irq(skb); - np->tx_skbuff[skbnr] = NULL; } static void nv_drain_tx(struct net_device *dev) @@ -981,10 +983,8 @@ static void nv_drain_tx(struct net_device *dev) np->tx_ring.orig[i].FlagLen = 0; else np->tx_ring.ex[i].FlagLen = 0; - if (np->tx_skbuff[i]) { - nv_release_txskb(dev, i); + if (nv_release_txskb(dev, i)) np->stats.tx_dropped++; - } } } @@ -1021,68 +1021,105 @@ static void drain_ring(struct net_device *dev) static int nv_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct fe_priv *np = netdev_priv(dev); + u32 tx_flags = 0; u32 tx_flags_extra = (np->desc_ver == DESC_VER_1 ? NV_TX_LASTPACKET : NV_TX2_LASTPACKET); unsigned int fragments = skb_shinfo(skb)->nr_frags; - unsigned int nr = (np->next_tx + fragments) % TX_RING; + unsigned int nr = (np->next_tx - 1) % TX_RING; + unsigned int start_nr = np->next_tx % TX_RING; unsigned int i; + u32 offset = 0; + u32 bcnt; + u32 size = skb->len-skb->data_len; + u32 entries = (size >> NV_TX2_TSO_MAX_SHIFT) + ((size & (NV_TX2_TSO_MAX_SIZE-1)) ? 1 : 0); + + /* add fragments to entries count */ + for (i = 0; i < fragments; i++) { + entries += (skb_shinfo(skb)->frags[i].size >> NV_TX2_TSO_MAX_SHIFT) + + ((skb_shinfo(skb)->frags[i].size & (NV_TX2_TSO_MAX_SIZE-1)) ? 1 : 0); + } spin_lock_irq(&np->lock); - if ((np->next_tx - np->nic_tx + fragments) > TX_LIMIT_STOP) { + if ((np->next_tx - np->nic_tx + entries - 1) > TX_LIMIT_STOP) { spin_unlock_irq(&np->lock); netif_stop_queue(dev); return NETDEV_TX_BUSY; } - np->tx_skbuff[nr] = skb; - - if (fragments) { - dprintk(KERN_DEBUG "%s: nv_start_xmit: buffer contains %d fragments\n", dev->name, fragments); - /* setup descriptors in reverse order */ - for (i = fragments; i >= 1; i--) { - skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; - np->tx_dma[nr] = pci_map_page(np->pci_dev, frag->page, frag->page_offset, frag->size, - PCI_DMA_TODEVICE); + /* setup the header buffer */ + do { + bcnt = (size > NV_TX2_TSO_MAX_SIZE) ? NV_TX2_TSO_MAX_SIZE : size; + nr = (nr + 1) % TX_RING; + + np->tx_dma[nr] = pci_map_single(np->pci_dev, skb->data + offset, bcnt, + PCI_DMA_TODEVICE); + np->tx_dma_len[nr] = bcnt; + + if (np->desc_ver == DESC_VER_1 || np->desc_ver == DESC_VER_2) { + np->tx_ring.orig[nr].PacketBuffer = cpu_to_le32(np->tx_dma[nr]); + np->tx_ring.orig[nr].FlagLen = cpu_to_le32((bcnt-1) | tx_flags); + } else { + np->tx_ring.ex[nr].PacketBufferHigh = cpu_to_le64(np->tx_dma[nr]) >> 32; + np->tx_ring.ex[nr].PacketBufferLow = cpu_to_le64(np->tx_dma[nr]) & 0x0FFFFFFFF; + np->tx_ring.ex[nr].FlagLen = cpu_to_le32((bcnt-1) | tx_flags); + } + tx_flags = np->tx_flags; + offset += bcnt; + size -= bcnt; + } while(size); + + /* setup the fragments */ + for (i = 0; i < fragments; i++) { + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + u32 size = frag->size; + offset = 0; + + do { + bcnt = (size > NV_TX2_TSO_MAX_SIZE) ? NV_TX2_TSO_MAX_SIZE : size; + nr = (nr + 1) % TX_RING; + + np->tx_dma[nr] = pci_map_page(np->pci_dev, frag->page, frag->page_offset+offset, bcnt, + PCI_DMA_TODEVICE); + np->tx_dma_len[nr] = bcnt; if (np->desc_ver == DESC_VER_1 || np->desc_ver == DESC_VER_2) { np->tx_ring.orig[nr].PacketBuffer = cpu_to_le32(np->tx_dma[nr]); - np->tx_ring.orig[nr].FlagLen = cpu_to_le32( (frag->size-1) | np->tx_flags | tx_flags_extra); + np->tx_ring.orig[nr].FlagLen = cpu_to_le32((bcnt-1) | tx_flags); } else { np->tx_ring.ex[nr].PacketBufferHigh = cpu_to_le64(np->tx_dma[nr]) >> 32; np->tx_ring.ex[nr].PacketBufferLow = cpu_to_le64(np->tx_dma[nr]) & 0x0FFFFFFFF; - np->tx_ring.ex[nr].FlagLen = cpu_to_le32( (frag->size-1) | np->tx_flags | tx_flags_extra); + np->tx_ring.ex[nr].FlagLen = cpu_to_le32((bcnt-1) | tx_flags); } - - nr = (nr - 1) % TX_RING; + offset += bcnt; + size -= bcnt; + } while (size); + } - if (np->desc_ver == DESC_VER_1) - tx_flags_extra &= ~NV_TX_LASTPACKET; - else - tx_flags_extra &= ~NV_TX2_LASTPACKET; - } + /* set last fragment flag */ + if (np->desc_ver == DESC_VER_1 || np->desc_ver == DESC_VER_2) { + np->tx_ring.orig[nr].FlagLen |= cpu_to_le32(tx_flags_extra); + } else { + np->tx_ring.ex[nr].FlagLen |= cpu_to_le32(tx_flags_extra); } + np->tx_skbuff[nr] = skb; + #ifdef NETIF_F_TSO if (skb_shinfo(skb)->tso_size) - tx_flags_extra |= NV_TX2_TSO | (skb_shinfo(skb)->tso_size << NV_TX2_TSO_SHIFT); + tx_flags_extra = NV_TX2_TSO | (skb_shinfo(skb)->tso_size << NV_TX2_TSO_SHIFT); else #endif - tx_flags_extra |= (skb->ip_summed == CHECKSUM_HW ? (NV_TX2_CHECKSUM_L3|NV_TX2_CHECKSUM_L4) : 0); + tx_flags_extra = (skb->ip_summed == CHECKSUM_HW ? (NV_TX2_CHECKSUM_L3|NV_TX2_CHECKSUM_L4) : 0); - np->tx_dma[nr] = pci_map_single(np->pci_dev, skb->data, skb->len-skb->data_len, - PCI_DMA_TODEVICE); - + /* set tx flags */ if (np->desc_ver == DESC_VER_1 || np->desc_ver == DESC_VER_2) { - np->tx_ring.orig[nr].PacketBuffer = cpu_to_le32(np->tx_dma[nr]); - np->tx_ring.orig[nr].FlagLen = cpu_to_le32( (skb->len-skb->data_len-1) | np->tx_flags | tx_flags_extra); + np->tx_ring.orig[start_nr].FlagLen |= cpu_to_le32(tx_flags | tx_flags_extra); } else { - np->tx_ring.ex[nr].PacketBufferHigh = cpu_to_le64(np->tx_dma[nr]) >> 32; - np->tx_ring.ex[nr].PacketBufferLow = cpu_to_le64(np->tx_dma[nr]) & 0x0FFFFFFFF; - np->tx_ring.ex[nr].FlagLen = cpu_to_le32( (skb->len-skb->data_len-1) | np->tx_flags | tx_flags_extra); + np->tx_ring.ex[start_nr].FlagLen |= cpu_to_le32(tx_flags | tx_flags_extra); } - dprintk(KERN_DEBUG "%s: nv_start_xmit: packet packet %d queued for transmission. tx_flags_extra: %x\n", - dev->name, np->next_tx, tx_flags_extra); + dprintk(KERN_DEBUG "%s: nv_start_xmit: packet %d (entries %d) queued for transmission. tx_flags_extra: %x\n", + dev->name, np->next_tx, entries, tx_flags_extra); { int j; for (j=0; j<64; j++) { @@ -1093,7 +1130,7 @@ static int nv_start_xmit(struct sk_buff *skb, struct net_device *dev) dprintk("\n"); } - np->next_tx += 1 + fragments; + np->next_tx += entries; dev->trans_start = jiffies; spin_unlock_irq(&np->lock); @@ -1140,7 +1177,6 @@ static void nv_tx_done(struct net_device *dev) np->stats.tx_packets++; np->stats.tx_bytes += skb->len; } - nv_release_txskb(dev, i); } } else { if (Flags & NV_TX2_LASTPACKET) { @@ -1156,9 +1192,9 @@ static void nv_tx_done(struct net_device *dev) np->stats.tx_packets++; np->stats.tx_bytes += skb->len; } - nv_release_txskb(dev, i); } } + nv_release_txskb(dev, i); np->nic_tx++; } if (np->next_tx - np->nic_tx < TX_LIMIT_START) @@ -2456,7 +2492,7 @@ static int __devinit nv_probe(struct pci_dev *pci_dev, const struct pci_device_i np->txrxctl_bits |= NVREG_TXRXCTL_RXCHECK; dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG; #ifdef NETIF_F_TSO - /* disabled dev->features |= NETIF_F_TSO; */ + dev->features |= NETIF_F_TSO; #endif } -- 2.39.5