sky2: Avoid rewinding sky2->tx_prod

Keep sky2->tx_prod consistent since int might be examined by
an softirq poll or restart.

Signed-off-by: Mike McCormack <mikem@ring3k.org>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index 1415a837509345bb215654183ec8c1e97fed034d..a52b8631783701f12fd9eec3bb7d2431415e1a9e 100644 (file)
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -989,11 +989,11 @@ static void sky2_prefetch_init(struct sky2_hw *hw, u32 qaddr,
        sky2_read32(hw, Y2_QADDR(qaddr, PREF_UNIT_CTRL));
 }
 
-static inline struct sky2_tx_le *get_tx_le(struct sky2_port *sky2)
+static inline struct sky2_tx_le *get_tx_le(struct sky2_port *sky2, u16 *slot)
 {
-       struct sky2_tx_le *le = sky2->tx_le + sky2->tx_prod;
+       struct sky2_tx_le *le = sky2->tx_le + *slot;
 
-       sky2->tx_prod = RING_NEXT(sky2->tx_prod, TX_RING_SIZE);
+       *slot = RING_NEXT(*slot, TX_RING_SIZE);
        le->ctrl = 0;
        return le;
 }
@@ -1006,7 +1006,7 @@ static void tx_init(struct sky2_port *sky2)
        sky2->tx_tcpsum = 0;
        sky2->tx_last_mss = 0;
 
-       le = get_tx_le(sky2);
+       le = get_tx_le(sky2, &sky2->tx_prod);
        le->addr = 0;
        le->opcode = OP_ADDR64 | HW_OWNER;
 }
@@ -1572,7 +1572,8 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev)
        struct sky2_hw *hw = sky2->hw;
        struct sky2_tx_le *le = NULL;
        struct tx_ring_info *re;
-       unsigned i, len, first_slot;
+       unsigned i, len;
+       u16 slot;
        dma_addr_t mapping;
        u16 mss;
        u8 ctrl;
@@ -1586,14 +1587,14 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev)
        if (pci_dma_mapping_error(hw->pdev, mapping))
                goto mapping_error;
 
-       first_slot = sky2->tx_prod;
+       slot = sky2->tx_prod;
        if (unlikely(netif_msg_tx_queued(sky2)))
                printk(KERN_DEBUG "%s: tx queued, slot %u, len %d\n",
-                      dev->name, first_slot, skb->len);
+                      dev->name, slot, skb->len);
 
        /* Send high bits if needed */
        if (sizeof(dma_addr_t) > sizeof(u32)) {
-               le = get_tx_le(sky2);
+               le = get_tx_le(sky2, &slot);
                le->addr = cpu_to_le32(upper_32_bits(mapping));
                le->opcode = OP_ADDR64 | HW_OWNER;
        }
@@ -1606,7 +1607,7 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev)
                        mss += ETH_HLEN + ip_hdrlen(skb) + tcp_hdrlen(skb);
 
                if (mss != sky2->tx_last_mss) {
-                       le = get_tx_le(sky2);
+                       le = get_tx_le(sky2, &slot);
                        le->addr = cpu_to_le32(mss);
 
                        if (hw->flags & SKY2_HW_NEW_LE)
@@ -1622,7 +1623,7 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev)
        /* Add VLAN tag, can piggyback on LRGLEN or ADDR64 */
        if (sky2->vlgrp && vlan_tx_tag_present(skb)) {
                if (!le) {
-                       le = get_tx_le(sky2);
+                       le = get_tx_le(sky2, &slot);
                        le->addr = 0;
                        le->opcode = OP_VLAN|HW_OWNER;
                } else
@@ -1651,7 +1652,7 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev)
                        if (tcpsum != sky2->tx_tcpsum) {
                                sky2->tx_tcpsum = tcpsum;
 
-                               le = get_tx_le(sky2);
+                               le = get_tx_le(sky2, &slot);
                                le->addr = cpu_to_le32(tcpsum);
                                le->length = 0; /* initial checksum value */
                                le->ctrl = 1;   /* one packet */
@@ -1660,7 +1661,7 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev)
                }
        }
 
-       le = get_tx_le(sky2);
+       le = get_tx_le(sky2, &slot);
        le->addr = cpu_to_le32((u32) mapping);
        le->length = cpu_to_le16(len);
        le->ctrl = ctrl;
@@ -1681,13 +1682,13 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev)
                        goto mapping_unwind;
 
                if (sizeof(dma_addr_t) > sizeof(u32)) {
-                       le = get_tx_le(sky2);
+                       le = get_tx_le(sky2, &slot);
                        le->addr = cpu_to_le32(upper_32_bits(mapping));
                        le->ctrl = 0;
                        le->opcode = OP_ADDR64 | HW_OWNER;
                }
 
-               le = get_tx_le(sky2);
+               le = get_tx_le(sky2, &slot);
                le->addr = cpu_to_le32((u32) mapping);
                le->length = cpu_to_le16(frag->size);
                le->ctrl = ctrl;
@@ -1701,6 +1702,8 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev)
 
        le->ctrl |= EOP;
 
+       sky2->tx_prod = slot;
+
        if (tx_avail(sky2) <= MAX_SKB_TX_LE)
                netif_stop_queue(dev);
 
@@ -1709,7 +1712,7 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev)
        return NETDEV_TX_OK;
 
 mapping_unwind:
-       for (i = first_slot; i != sky2->tx_prod; i = RING_NEXT(i, TX_RING_SIZE)) {
+       for (i = sky2->tx_prod; i != slot; i = RING_NEXT(i, TX_RING_SIZE)) {
                le = sky2->tx_le + i;
                re = sky2->tx_ring + i;
 
@@ -1729,7 +1732,6 @@ mapping_unwind:
                }
        }
 
-       sky2->tx_prod = first_slot;
 mapping_error:
        if (net_ratelimit())
                dev_warn(&hw->pdev->dev, "%s: tx mapping error\n", dev->name);