From ee4aa8df70fa6d76bd776c025dc0d8d746c18317 Mon Sep 17 00:00:00 2001 From: Neil Horman Date: Wed, 3 Jan 2018 13:09:23 -0500 Subject: [PATCH] 3c59x: fix missing dma_mapping_error check and bad ring refill logic A few spots in 3c59x missed calls to dma_mapping_error checks, casuing WARN_ONS to trigger. Clean those up. While we're at it, refactor the refill code a bit so that if skb allocation or dma mapping fails, we recycle the existing buffer. This prevents holes in the rx ring, and makes for much simpler logic Note: This is compile only tested. Ted, if you could run this and confirm that it continues to work properly, I would appreciate it, as I currently don't have access to this hardware Signed-off-by: Neil Horman CC: Steffen Klassert CC: "David S. Miller" Reported-by: tedheadster@gmail.com Signed-off-by: David S. Miller --- drivers/net/ethernet/3com/3c59x.c | 90 +++++++++++++++++---------------------- 1 file changed, 38 insertions(+), 52 deletions(-) diff --git a/drivers/net/ethernet/3com/3c59x.c b/drivers/net/ethernet/3com/3c59x.c index f4e13a7..36c8950 100644 --- a/drivers/net/ethernet/3com/3c59x.c +++ b/drivers/net/ethernet/3com/3c59x.c @@ -602,7 +602,7 @@ struct vortex_private { struct sk_buff* rx_skbuff[RX_RING_SIZE]; struct sk_buff* tx_skbuff[TX_RING_SIZE]; unsigned int cur_rx, cur_tx; /* The next free ring entry */ - unsigned int dirty_rx, dirty_tx; /* The ring entries to be free()ed. */ + unsigned int dirty_tx; /* The ring entries to be free()ed. */ struct vortex_extra_stats xstats; /* NIC-specific extra stats */ struct sk_buff *tx_skb; /* Packet being eaten by bus master ctrl. */ dma_addr_t tx_skb_dma; /* Allocated DMA address for bus master ctrl DMA. */ @@ -618,7 +618,6 @@ struct vortex_private { /* The remainder are related to chip state, mostly media selection. */ struct timer_list timer; /* Media selection timer. */ - struct timer_list rx_oom_timer; /* Rx skb allocation retry timer */ int options; /* User-settable misc. driver options. */ unsigned int media_override:4, /* Passed-in media type. */ default_media:4, /* Read from the EEPROM/Wn3_Config. */ @@ -760,7 +759,6 @@ static void mdio_sync(struct vortex_private *vp, int bits); static int mdio_read(struct net_device *dev, int phy_id, int location); static void mdio_write(struct net_device *vp, int phy_id, int location, int value); static void vortex_timer(struct timer_list *t); -static void rx_oom_timer(struct timer_list *t); static netdev_tx_t vortex_start_xmit(struct sk_buff *skb, struct net_device *dev); static netdev_tx_t boomerang_start_xmit(struct sk_buff *skb, @@ -1601,7 +1599,6 @@ vortex_up(struct net_device *dev) timer_setup(&vp->timer, vortex_timer, 0); mod_timer(&vp->timer, RUN_AT(media_tbl[dev->if_port].wait)); - timer_setup(&vp->rx_oom_timer, rx_oom_timer, 0); if (vortex_debug > 1) pr_debug("%s: Initial media type %s.\n", @@ -1676,7 +1673,7 @@ vortex_up(struct net_device *dev) window_write16(vp, 0x0040, 4, Wn4_NetDiag); if (vp->full_bus_master_rx) { /* Boomerang bus master. */ - vp->cur_rx = vp->dirty_rx = 0; + vp->cur_rx = 0; /* Initialize the RxEarly register as recommended. */ iowrite16(SetRxThreshold + (1536>>2), ioaddr + EL3_CMD); iowrite32(0x0020, ioaddr + PktStatus); @@ -1729,6 +1726,7 @@ vortex_open(struct net_device *dev) struct vortex_private *vp = netdev_priv(dev); int i; int retval; + dma_addr_t dma; /* Use the now-standard shared IRQ implementation. */ if ((retval = request_irq(dev->irq, vp->full_bus_master_rx ? @@ -1753,7 +1751,11 @@ vortex_open(struct net_device *dev) break; /* Bad news! */ skb_reserve(skb, NET_IP_ALIGN); /* Align IP on 16 byte boundaries */ - vp->rx_ring[i].addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->data, PKT_BUF_SZ, PCI_DMA_FROMDEVICE)); + dma = pci_map_single(VORTEX_PCI(vp), skb->data, + PKT_BUF_SZ, PCI_DMA_FROMDEVICE); + if (dma_mapping_error(&VORTEX_PCI(vp)->dev, dma)) + break; + vp->rx_ring[i].addr = cpu_to_le32(dma); } if (i != RX_RING_SIZE) { pr_emerg("%s: no memory for rx ring\n", dev->name); @@ -2067,6 +2069,12 @@ vortex_start_xmit(struct sk_buff *skb, struct net_device *dev) int len = (skb->len + 3) & ~3; vp->tx_skb_dma = pci_map_single(VORTEX_PCI(vp), skb->data, len, PCI_DMA_TODEVICE); + if (dma_mapping_error(&VORTEX_PCI(vp)->dev, vp->tx_skb_dma)) { + dev_kfree_skb_any(skb); + dev->stats.tx_dropped++; + return NETDEV_TX_OK; + } + spin_lock_irq(&vp->window_lock); window_set(vp, 7); iowrite32(vp->tx_skb_dma, ioaddr + Wn7_MasterAddr); @@ -2593,7 +2601,7 @@ boomerang_rx(struct net_device *dev) int entry = vp->cur_rx % RX_RING_SIZE; void __iomem *ioaddr = vp->ioaddr; int rx_status; - int rx_work_limit = vp->dirty_rx + RX_RING_SIZE - vp->cur_rx; + int rx_work_limit = RX_RING_SIZE; if (vortex_debug > 5) pr_debug("boomerang_rx(): status %4.4x\n", ioread16(ioaddr+EL3_STATUS)); @@ -2614,7 +2622,8 @@ boomerang_rx(struct net_device *dev) } else { /* The packet length: up to 4.5K!. */ int pkt_len = rx_status & 0x1fff; - struct sk_buff *skb; + struct sk_buff *skb, *newskb; + dma_addr_t newdma; dma_addr_t dma = le32_to_cpu(vp->rx_ring[entry].addr); if (vortex_debug > 4) @@ -2633,9 +2642,27 @@ boomerang_rx(struct net_device *dev) pci_dma_sync_single_for_device(VORTEX_PCI(vp), dma, PKT_BUF_SZ, PCI_DMA_FROMDEVICE); vp->rx_copy++; } else { + /* Pre-allocate the replacement skb. If it or its + * mapping fails then recycle the buffer thats already + * in place + */ + newskb = netdev_alloc_skb_ip_align(dev, PKT_BUF_SZ); + if (!newskb) { + dev->stats.rx_dropped++; + goto clear_complete; + } + newdma = pci_map_single(VORTEX_PCI(vp), newskb->data, + PKT_BUF_SZ, PCI_DMA_FROMDEVICE); + if (dma_mapping_error(&VORTEX_PCI(vp)->dev, newdma)) { + dev->stats.rx_dropped++; + consume_skb(newskb); + goto clear_complete; + } + /* Pass up the skbuff already on the Rx ring. */ skb = vp->rx_skbuff[entry]; - vp->rx_skbuff[entry] = NULL; + vp->rx_skbuff[entry] = newskb; + vp->rx_ring[entry].addr = cpu_to_le32(newdma); skb_put(skb, pkt_len); pci_unmap_single(VORTEX_PCI(vp), dma, PKT_BUF_SZ, PCI_DMA_FROMDEVICE); vp->rx_nocopy++; @@ -2653,55 +2680,15 @@ boomerang_rx(struct net_device *dev) netif_rx(skb); dev->stats.rx_packets++; } - entry = (++vp->cur_rx) % RX_RING_SIZE; - } - /* Refill the Rx ring buffers. */ - for (; vp->cur_rx - vp->dirty_rx > 0; vp->dirty_rx++) { - struct sk_buff *skb; - entry = vp->dirty_rx % RX_RING_SIZE; - if (vp->rx_skbuff[entry] == NULL) { - skb = netdev_alloc_skb_ip_align(dev, PKT_BUF_SZ); - if (skb == NULL) { - static unsigned long last_jif; - if (time_after(jiffies, last_jif + 10 * HZ)) { - pr_warn("%s: memory shortage\n", - dev->name); - last_jif = jiffies; - } - if ((vp->cur_rx - vp->dirty_rx) == RX_RING_SIZE) - mod_timer(&vp->rx_oom_timer, RUN_AT(HZ * 1)); - break; /* Bad news! */ - } - vp->rx_ring[entry].addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->data, PKT_BUF_SZ, PCI_DMA_FROMDEVICE)); - vp->rx_skbuff[entry] = skb; - } +clear_complete: vp->rx_ring[entry].status = 0; /* Clear complete bit. */ iowrite16(UpUnstall, ioaddr + EL3_CMD); + entry = (++vp->cur_rx) % RX_RING_SIZE; } return 0; } -/* - * If we've hit a total OOM refilling the Rx ring we poll once a second - * for some memory. Otherwise there is no way to restart the rx process. - */ -static void -rx_oom_timer(struct timer_list *t) -{ - struct vortex_private *vp = from_timer(vp, t, rx_oom_timer); - struct net_device *dev = vp->mii.dev; - - spin_lock_irq(&vp->lock); - if ((vp->cur_rx - vp->dirty_rx) == RX_RING_SIZE) /* This test is redundant, but makes me feel good */ - boomerang_rx(dev); - if (vortex_debug > 1) { - pr_debug("%s: rx_oom_timer %s\n", dev->name, - ((vp->cur_rx - vp->dirty_rx) != RX_RING_SIZE) ? "succeeded" : "retrying"); - } - spin_unlock_irq(&vp->lock); -} - static void vortex_down(struct net_device *dev, int final_down) { @@ -2711,7 +2698,6 @@ vortex_down(struct net_device *dev, int final_down) netdev_reset_queue(dev); netif_stop_queue(dev); - del_timer_sync(&vp->rx_oom_timer); del_timer_sync(&vp->timer); /* Turn off statistics ASAP. We update dev->stats below. */ -- 2.7.4