| Message ID | 20210701011728.22626-3-vfedorenko@novek.ru |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Remove duplicate code around MTU | expand |
On 6/30/21 7:17 PM, Vadim Fedorenko wrote: > Consolidate IPv4 MTU code the same way it is done in IPv6 to have code > aligned in both address families > > Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> > --- > include/net/ip.h | 22 ++++++++++++++++++---- > net/ipv4/route.c | 21 +-------------------- > 2 files changed, 19 insertions(+), 24 deletions(-) > > diff --git a/include/net/ip.h b/include/net/ip.h > index d9683bef8684..ed261f2a40ac 100644 > --- a/include/net/ip.h > +++ b/include/net/ip.h > @@ -436,18 +436,32 @@ static inline bool ip_sk_ignore_df(const struct sock *sk) > static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, > bool forwarding) > { > + const struct rtable *rt = (const struct rtable *)dst; I realize this a code move from ipv4_mtu, but please use container_of here; I have been removing the typecasts as code is changed. > struct net *net = dev_net(dst->dev); > unsigned int mtu; > > if (net->ipv4.sysctl_ip_fwd_use_pmtu || > ip_mtu_locked(dst) || > - !forwarding) > - return dst_mtu(dst); > + !forwarding) { > + mtu = rt->rt_pmtu; > + if (mtu && time_before(jiffies, rt->dst.expires)) > + goto out; > + } > > /* 'forwarding = true' case should always honour route mtu */ > mtu = dst_metric_raw(dst, RTAX_MTU); > - if (!mtu) > - mtu = min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU); > + if (mtu) > + goto out; > + > + mtu = READ_ONCE(dst->dev->mtu); > + > + if (unlikely(ip_mtu_locked(dst))) { > + if (rt->rt_uses_gateway && mtu > 576) > + mtu = 576; > + } > + > +out: > + mtu = min_t(unsigned int, mtu, IP_MAX_MTU); > > return mtu - lwtunnel_headroom(dst->lwtstate, mtu); > } > diff --git a/net/ipv4/route.c b/net/ipv4/route.c > index 99c06944501a..04754d55b3c1 100644 > --- a/net/ipv4/route.c > +++ b/net/ipv4/route.c > @@ -1299,26 +1299,7 @@ static unsigned int ipv4_default_advmss(const struct dst_entry *dst) > > INDIRECT_CALLABLE_SCOPE unsigned int ipv4_mtu(const struct dst_entry *dst) > { > - const struct rtable *rt = (const struct rtable *)dst; > - unsigned int mtu = rt->rt_pmtu; > - > - if (!mtu || time_after_eq(jiffies, rt->dst.expires)) > - mtu = dst_metric_raw(dst, RTAX_MTU); > - > - if (mtu) > - goto out; > - > - mtu = READ_ONCE(dst->dev->mtu); > - > - if (unlikely(ip_mtu_locked(dst))) { > - if (rt->rt_uses_gateway && mtu > 576) > - mtu = 576; > - } > - > -out: > - mtu = min_t(unsigned int, mtu, IP_MAX_MTU); > - > - return mtu - lwtunnel_headroom(dst->lwtstate, mtu); > + return ip_dst_mtu_maybe_forward(dst, false); > } > EXPORT_INDIRECT_CALLABLE(ipv4_mtu); > >
On 01.07.2021 02:40, David Ahern wrote: > On 6/30/21 7:17 PM, Vadim Fedorenko wrote: >> Consolidate IPv4 MTU code the same way it is done in IPv6 to have code >> aligned in both address families >> >> Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> >> --- >> include/net/ip.h | 22 ++++++++++++++++++---- >> net/ipv4/route.c | 21 +-------------------- >> 2 files changed, 19 insertions(+), 24 deletions(-) >> >> diff --git a/include/net/ip.h b/include/net/ip.h >> index d9683bef8684..ed261f2a40ac 100644 >> --- a/include/net/ip.h >> +++ b/include/net/ip.h >> @@ -436,18 +436,32 @@ static inline bool ip_sk_ignore_df(const struct sock *sk) >> static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, >> bool forwarding) >> { >> + const struct rtable *rt = (const struct rtable *)dst; > > I realize this a code move from ipv4_mtu, but please use container_of > here; I have been removing the typecasts as code is changed. > No problem, I will change in next iteration
diff --git a/include/net/ip.h b/include/net/ip.h index d9683bef8684..ed261f2a40ac 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -436,18 +436,32 @@ static inline bool ip_sk_ignore_df(const struct sock *sk) static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, bool forwarding) { + const struct rtable *rt = (const struct rtable *)dst; struct net *net = dev_net(dst->dev); unsigned int mtu; if (net->ipv4.sysctl_ip_fwd_use_pmtu || ip_mtu_locked(dst) || - !forwarding) - return dst_mtu(dst); + !forwarding) { + mtu = rt->rt_pmtu; + if (mtu && time_before(jiffies, rt->dst.expires)) + goto out; + } /* 'forwarding = true' case should always honour route mtu */ mtu = dst_metric_raw(dst, RTAX_MTU); - if (!mtu) - mtu = min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU); + if (mtu) + goto out; + + mtu = READ_ONCE(dst->dev->mtu); + + if (unlikely(ip_mtu_locked(dst))) { + if (rt->rt_uses_gateway && mtu > 576) + mtu = 576; + } + +out: + mtu = min_t(unsigned int, mtu, IP_MAX_MTU); return mtu - lwtunnel_headroom(dst->lwtstate, mtu); } diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 99c06944501a..04754d55b3c1 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1299,26 +1299,7 @@ static unsigned int ipv4_default_advmss(const struct dst_entry *dst) INDIRECT_CALLABLE_SCOPE unsigned int ipv4_mtu(const struct dst_entry *dst) { - const struct rtable *rt = (const struct rtable *)dst; - unsigned int mtu = rt->rt_pmtu; - - if (!mtu || time_after_eq(jiffies, rt->dst.expires)) - mtu = dst_metric_raw(dst, RTAX_MTU); - - if (mtu) - goto out; - - mtu = READ_ONCE(dst->dev->mtu); - - if (unlikely(ip_mtu_locked(dst))) { - if (rt->rt_uses_gateway && mtu > 576) - mtu = 576; - } - -out: - mtu = min_t(unsigned int, mtu, IP_MAX_MTU); - - return mtu - lwtunnel_headroom(dst->lwtstate, mtu); + return ip_dst_mtu_maybe_forward(dst, false); } EXPORT_INDIRECT_CALLABLE(ipv4_mtu);
Consolidate IPv4 MTU code the same way it is done in IPv6 to have code aligned in both address families Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> --- include/net/ip.h | 22 ++++++++++++++++++---- net/ipv4/route.c | 21 +-------------------- 2 files changed, 19 insertions(+), 24 deletions(-)