[PATCH net-next 03/14] net: ipv4: ipmr: Split ipmr_queue_xmit() in two
From: Petr Machata <petrm@nvidia.com>
Date: 2025-06-09 20:51:50
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
Some of the work of ipmr_queue_xmit() is specific to IPMR forwarding, and should not take place on the output path. In order to allow reuse of the common parts, split the function into two: the ipmr_prepare_xmit() helper that takes care of the common bits, and the ipmr_queue_fwd_xmit(), which invokes the former and encapsulates the whole forwarding algorithm. Signed-off-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> --- net/ipv4/ipmr.c | 45 +++++++++++++++++++++++++++++---------------- 1 file changed, 29 insertions(+), 16 deletions(-)
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 1c5e6167cd76..7c1045d67ea8 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c@@ -1853,8 +1853,8 @@ static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt, /* Processing handlers for ipmr_forward, under rcu_read_lock() */ -static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt, - int in_vifi, struct sk_buff *skb, int vifi) +static int ipmr_prepare_xmit(struct net *net, struct mr_table *mrt, + struct sk_buff *skb, int vifi) { const struct iphdr *iph = ip_hdr(skb); struct vif_device *vif = &mrt->vif_table[vifi];
@@ -1865,7 +1865,7 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt, vif_dev = vif_dev_read(vif); if (!vif_dev) - goto out_free; + return -1; if (vif->flags & VIFF_REGISTER) { WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
@@ -1873,12 +1873,9 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt, DEV_STATS_ADD(vif_dev, tx_bytes, skb->len); DEV_STATS_INC(vif_dev, tx_packets); ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT); - goto out_free; + return -1; } - if (ipmr_forward_offloaded(skb, mrt, in_vifi, vifi)) - goto out_free; - if (vif->flags & VIFF_TUNNEL) { rt = ip_route_output_ports(net, &fl4, NULL, vif->remote, vif->local,
@@ -1886,7 +1883,7 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt, IPPROTO_IPIP, iph->tos & INET_DSCP_MASK, vif->link); if (IS_ERR(rt)) - goto out_free; + return -1; encap = sizeof(struct iphdr); } else { rt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
@@ -1894,7 +1891,7 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt, IPPROTO_IPIP, iph->tos & INET_DSCP_MASK, vif->link); if (IS_ERR(rt)) - goto out_free; + return -1; } if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
@@ -1904,14 +1901,14 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt, */ IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS); ip_rt_put(rt); - goto out_free; + return -1; } encap += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len; if (skb_cow(skb, encap)) { ip_rt_put(rt); - goto out_free; + return -1; } WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
@@ -1931,6 +1928,22 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt, DEV_STATS_ADD(vif_dev, tx_bytes, skb->len); } + return 0; +} + +static void ipmr_queue_fwd_xmit(struct net *net, struct mr_table *mrt, + int in_vifi, struct sk_buff *skb, int vifi) +{ + struct rtable *rt; + + if (ipmr_forward_offloaded(skb, mrt, in_vifi, vifi)) + goto out_free; + + if (ipmr_prepare_xmit(net, mrt, skb, vifi)) + goto out_free; + + rt = skb_rtable(skb); + IPCB(skb)->flags |= IPSKB_FORWARDED; /* RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
@@ -2062,8 +2075,8 @@ static void ip_mr_forward(struct net *net, struct mr_table *mrt, struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); if (skb2) - ipmr_queue_xmit(net, mrt, true_vifi, - skb2, psend); + ipmr_queue_fwd_xmit(net, mrt, true_vifi, + skb2, psend); } psend = ct; }
@@ -2074,10 +2087,10 @@ static void ip_mr_forward(struct net *net, struct mr_table *mrt, struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); if (skb2) - ipmr_queue_xmit(net, mrt, true_vifi, skb2, - psend); + ipmr_queue_fwd_xmit(net, mrt, true_vifi, skb2, + psend); } else { - ipmr_queue_xmit(net, mrt, true_vifi, skb, psend); + ipmr_queue_fwd_xmit(net, mrt, true_vifi, skb, psend); return; } }
--
2.49.0