From 14bbd6a565e1bcdc240d44687edb93f721cfdf99 Mon Sep 17 00:00:00 2001 From: Pravin B Shelar Date: Thu, 14 Feb 2013 09:44:49 +0000 Subject: [PATCH] net: Add skb_unclone() helper function. This function will be used in next GRE_GSO patch. This patch does not change any functionality. Signed-off-by: Pravin B Shelar Acked-by: Eric Dumazet --- drivers/net/ppp/ppp_generic.c | 3 +-- include/linux/skbuff.h | 10 ++++++++++ net/ipv4/ah4.c | 3 +-- net/ipv4/ip_fragment.c | 2 +- net/ipv4/tcp_output.c | 2 +- net/ipv4/xfrm4_input.c | 2 +- net/ipv4/xfrm4_mode_tunnel.c | 3 +-- net/ipv6/ah6.c | 3 +-- net/ipv6/netfilter/nf_conntrack_reasm.c | 2 +- net/ipv6/reassembly.c | 2 +- net/ipv6/xfrm6_mode_tunnel.c | 3 +-- net/sched/act_ipt.c | 6 ++---- net/sched/act_pedit.c | 3 +-- 13 files changed, 23 insertions(+), 21 deletions(-) diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 0b2706abe3e3..4fd754e74eb2 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -1805,8 +1805,7 @@ ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb) /* the filter instructions are constructed assuming a four-byte PPP header on each packet */ if (ppp->pass_filter || ppp->active_filter) { - if (skb_cloned(skb) && - pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) + if (skb_unclone(skb, GFP_ATOMIC)) goto err; *skb_push(skb, 2) = 0; diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 9da99520ccd5..ca6ee7d93edb 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -804,6 +804,16 @@ static inline int skb_cloned(const struct sk_buff *skb) (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1; } +static inline int skb_unclone(struct sk_buff *skb, gfp_t pri) +{ + might_sleep_if(pri & __GFP_WAIT); + + if (skb_cloned(skb)) + return pskb_expand_head(skb, 0, 0, pri); + + return 0; +} + /** * skb_header_cloned - is the header a clone * @skb: buffer to check diff --git a/net/ipv4/ah4.c b/net/ipv4/ah4.c index a69b4e4a02b5..2e7f1948216f 100644 --- a/net/ipv4/ah4.c +++ b/net/ipv4/ah4.c @@ -321,8 +321,7 @@ static int ah_input(struct xfrm_state *x, struct sk_buff *skb) /* We are going to _remove_ AH header to keep sockets happy, * so... Later this can change. */ - if (skb_cloned(skb) && - pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) + if (skb_unclone(skb, GFP_ATOMIC)) goto out; skb->ip_summed = CHECKSUM_NONE; diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index 1211613c6c34..b6d30acb600c 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -590,7 +590,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, goto out_oversize; /* Head of list must not be cloned. */ - if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) + if (skb_unclone(head, GFP_ATOMIC)) goto out_nomem; /* If the first fragment is fragmented itself, we split diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 6182d90e97b0..fd0cea114b5d 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1331,7 +1331,7 @@ static void __pskb_trim_head(struct sk_buff *skb, int len) /* Remove acked data from a packet in the transmit queue. */ int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len) { - if (skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) + if (skb_unclone(skb, GFP_ATOMIC)) return -ENOMEM; __pskb_trim_head(skb, len); diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c index 06814b6216dc..1f12c8b45864 100644 --- a/net/ipv4/xfrm4_input.c +++ b/net/ipv4/xfrm4_input.c @@ -132,7 +132,7 @@ int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb) * header and optional ESP marker bytes) and then modify the * protocol to ESP, and then call into the transform receiver. */ - if (skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) + if (skb_unclone(skb, GFP_ATOMIC)) goto drop; /* Now we can update and verify the packet length... */ diff --git a/net/ipv4/xfrm4_mode_tunnel.c b/net/ipv4/xfrm4_mode_tunnel.c index ddee0a099a2c..1162ace30838 100644 --- a/net/ipv4/xfrm4_mode_tunnel.c +++ b/net/ipv4/xfrm4_mode_tunnel.c @@ -142,8 +142,7 @@ static int xfrm4_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb) for_each_input_rcu(rcv_notify_handlers, handler) handler->handler(skb); - if (skb_cloned(skb) && - (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) + if (err = skb_unclone(skb, GFP_ATOMIC)) goto out; if (x->props.flags & XFRM_STATE_DECAP_DSCP) diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c index 384233188ac1..bb02e176cb70 100644 --- a/net/ipv6/ah6.c +++ b/net/ipv6/ah6.c @@ -521,8 +521,7 @@ static int ah6_input(struct xfrm_state *x, struct sk_buff *skb) /* We are going to _remove_ AH header to keep sockets happy, * so... Later this can change. */ - if (skb_cloned(skb) && - pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) + if (skb_unclone(skb, GFP_ATOMIC)) goto out; skb->ip_summed = CHECKSUM_NONE; diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index c674f158efa8..b89a8c3186cd 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -368,7 +368,7 @@ nf_ct_frag6_reasm(struct frag_queue *fq, struct net_device *dev) } /* Head of list must not be cloned. */ - if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) { + if (skb_unclone(head, GFP_ATOMIC)) { pr_debug("skb is cloned but can't expand head"); goto out_oom; } diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c index bab2c270f292..e354743ed426 100644 --- a/net/ipv6/reassembly.c +++ b/net/ipv6/reassembly.c @@ -404,7 +404,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev, goto out_oversize; /* Head of list must not be cloned. */ - if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) + if (skb_unclone(head, GFP_ATOMIC)) goto out_oom; /* If the first fragment is fragmented itself, we split diff --git a/net/ipv6/xfrm6_mode_tunnel.c b/net/ipv6/xfrm6_mode_tunnel.c index 9f2095b19ad0..93c41a81c4c3 100644 --- a/net/ipv6/xfrm6_mode_tunnel.c +++ b/net/ipv6/xfrm6_mode_tunnel.c @@ -69,8 +69,7 @@ static int xfrm6_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb) if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) goto out; - if (skb_cloned(skb) && - (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) + if (err = skb_unclone(skb, GFP_ATOMIC)) goto out; if (x->props.flags & XFRM_STATE_DECAP_DSCP) diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c index 0fb9e3f567e6..e0f6de64afec 100644 --- a/net/sched/act_ipt.c +++ b/net/sched/act_ipt.c @@ -207,10 +207,8 @@ static int tcf_ipt(struct sk_buff *skb, const struct tc_action *a, struct tcf_ipt *ipt = a->priv; struct xt_action_param par; - if (skb_cloned(skb)) { - if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) - return TC_ACT_UNSPEC; - } + if (skb_unclone(skb, GFP_ATOMIC)) + return TC_ACT_UNSPEC; spin_lock(&ipt->tcf_lock); diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c index 0c3faddf3f2c..7ed78c9e505c 100644 --- a/net/sched/act_pedit.c +++ b/net/sched/act_pedit.c @@ -131,8 +131,7 @@ static int tcf_pedit(struct sk_buff *skb, const struct tc_action *a, int i, munged = 0; unsigned int off; - if (skb_cloned(skb) && - pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) + if (skb_unclone(skb, GFP_ATOMIC)) return p->tcf_action; off = skb_network_offset(skb);