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	igmp: refine skb allocations
IGMP allocates MTU sized skbs. This may fail for large MTU (order-2 allocations), so add a fallback to try lower sizes. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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					 1 changed files with 13 additions and 4 deletions
				
			
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			@ -300,6 +300,8 @@ igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
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	return scount;
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}
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#define igmp_skb_size(skb) (*(unsigned int *)((skb)->cb))
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static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
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{
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	struct sk_buff *skb;
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			@ -308,9 +310,16 @@ static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
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	struct igmpv3_report *pig;
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	struct net *net = dev_net(dev);
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	skb = alloc_skb(size + LL_ALLOCATED_SPACE(dev), GFP_ATOMIC);
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	if (skb == NULL)
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		return NULL;
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	while (1) {
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		skb = alloc_skb(size + LL_ALLOCATED_SPACE(dev),
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				GFP_ATOMIC | __GFP_NOWARN);
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		if (skb)
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			break;
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		size >>= 1;
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		if (size < 256)
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			return NULL;
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	}
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	igmp_skb_size(skb) = size;
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	{
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		struct flowi fl = { .oif = dev->ifindex,
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			@ -399,7 +408,7 @@ static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
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	return skb;
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}
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#define AVAILABLE(skb) ((skb) ? ((skb)->dev ? (skb)->dev->mtu - (skb)->len : \
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#define AVAILABLE(skb) ((skb) ? ((skb)->dev ? igmp_skb_size(skb) - (skb)->len : \
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	skb_tailroom(skb)) : 0)
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static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
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