From 39ca5bb76f3382b1cb0062d75ec45abd1c46e6d2 Mon Sep 17 00:00:00 2001 From: Christian Lamparter Date: Tue, 9 Dec 2008 21:09:00 +0100 Subject: [PATCH] p54: enforce strict tx_queue limits The patch fixes an old FIXME in p54pci.c by moving the "queue full" check into the common library, where we can deal with it properly. Signed-off-by: Christian Lamparter Signed-off-by: John W. Linville --- drivers/net/wireless/p54/p54common.c | 22 +++++++++++++++++++++- drivers/net/wireless/p54/p54pci.c | 7 ------- 2 files changed, 21 insertions(+), 8 deletions(-) diff --git a/drivers/net/wireless/p54/p54common.c b/drivers/net/wireless/p54/p54common.c index 409ae930d766..fac6b416e9e9 100644 --- a/drivers/net/wireless/p54/p54common.c +++ b/drivers/net/wireless/p54/p54common.c @@ -874,7 +874,27 @@ static int p54_assign_address(struct ieee80211_hw *dev, struct sk_buff *skb, return -EINVAL; spin_lock_irqsave(&priv->tx_queue.lock, flags); + left = skb_queue_len(&priv->tx_queue); + if (unlikely(left >= 28)) { + /* + * The tx_queue is nearly full! + * We have throttle normal data traffic, because we must + * have a few spare slots for control frames left. + */ + ieee80211_stop_queues(dev); + + if (unlikely(left == 32)) { + /* + * The tx_queue is now really full. + * + * TODO: check if the device has crashed and reset it. + */ + spin_unlock_irqrestore(&priv->tx_queue.lock, flags); + return -ENOSPC; + } + } + while (left--) { u32 hole_size; info = IEEE80211_SKB_CB(entry); @@ -903,7 +923,7 @@ static int p54_assign_address(struct ieee80211_hw *dev, struct sk_buff *skb, if (!target_skb) { spin_unlock_irqrestore(&priv->tx_queue.lock, flags); ieee80211_stop_queues(dev); - return -ENOMEM; + return -ENOSPC; } info = IEEE80211_SKB_CB(skb); diff --git a/drivers/net/wireless/p54/p54pci.c b/drivers/net/wireless/p54/p54pci.c index d21c509325fe..c28220e401b9 100644 --- a/drivers/net/wireless/p54/p54pci.c +++ b/drivers/net/wireless/p54/p54pci.c @@ -332,13 +332,6 @@ static void p54p_tx(struct ieee80211_hw *dev, struct sk_buff *skb, P54P_WRITE(dev_int, cpu_to_le32(ISL38XX_DEV_INT_UPDATE)); P54P_READ(dev_int); - - /* FIXME: unlikely to happen because the device usually runs out of - memory before we fill the ring up, but we can make it impossible */ - if (idx - device_idx > ARRAY_SIZE(ring_control->tx_data) - 2) { - p54_free_skb(dev, skb); - printk(KERN_INFO "%s: tx overflow.\n", wiphy_name(dev->wiphy)); - } } static void p54p_stop(struct ieee80211_hw *dev) -- 2.30.2