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Diffstat (limited to 'net/ipv4/tcp_output.c')
-rw-r--r--net/ipv4/tcp_output.c73
1 files changed, 67 insertions, 6 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index b62b59b18db9..306e25d743e8 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -38,6 +38,7 @@
#define pr_fmt(fmt) "TCP: " fmt
#include <net/tcp.h>
+#include <net/mptcp.h>
#include <linux/compiler.h>
#include <linux/gfp.h>
@@ -414,6 +415,7 @@ static inline bool tcp_urg_mode(const struct tcp_sock *tp)
#define OPTION_WSCALE (1 << 3)
#define OPTION_FAST_OPEN_COOKIE (1 << 8)
#define OPTION_SMC (1 << 9)
+#define OPTION_MPTCP (1 << 10)
static void smc_options_write(__be32 *ptr, u16 *options)
{
@@ -439,8 +441,17 @@ struct tcp_out_options {
__u8 *hash_location; /* temporary pointer, overloaded */
__u32 tsval, tsecr; /* need to include OPTION_TS */
struct tcp_fastopen_cookie *fastopen_cookie; /* Fast open cookie */
+ struct mptcp_out_options mptcp;
};
+static void mptcp_options_write(__be32 *ptr, struct tcp_out_options *opts)
+{
+#if IS_ENABLED(CONFIG_MPTCP)
+ if (unlikely(OPTION_MPTCP & opts->options))
+ mptcp_write_options(ptr, &opts->mptcp);
+#endif
+}
+
/* Write previously computed TCP options to the packet.
*
* Beware: Something in the Internet is very sensitive to the ordering of
@@ -549,6 +560,8 @@ static void tcp_options_write(__be32 *ptr, struct tcp_sock *tp,
}
smc_options_write(ptr, &options);
+
+ mptcp_options_write(ptr, opts);
}
static void smc_set_option(const struct tcp_sock *tp,
@@ -584,6 +597,22 @@ static void smc_set_option_cond(const struct tcp_sock *tp,
#endif
}
+static void mptcp_set_option_cond(const struct request_sock *req,
+ struct tcp_out_options *opts,
+ unsigned int *remaining)
+{
+ if (rsk_is_mptcp(req)) {
+ unsigned int size;
+
+ if (mptcp_synack_options(req, &size, &opts->mptcp)) {
+ if (*remaining >= size) {
+ opts->options |= OPTION_MPTCP;
+ *remaining -= size;
+ }
+ }
+ }
+}
+
/* Compute TCP options for SYN packets. This is not the final
* network wire format yet.
*/
@@ -653,6 +682,15 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb,
smc_set_option(tp, opts, &remaining);
+ if (sk_is_mptcp(sk)) {
+ unsigned int size;
+
+ if (mptcp_syn_options(sk, skb, &size, &opts->mptcp)) {
+ opts->options |= OPTION_MPTCP;
+ remaining -= size;
+ }
+ }
+
return MAX_TCP_OPTION_SPACE - remaining;
}
@@ -714,6 +752,8 @@ static unsigned int tcp_synack_options(const struct sock *sk,
}
}
+ mptcp_set_option_cond(req, opts, &remaining);
+
smc_set_option_cond(tcp_sk(sk), ireq, opts, &remaining);
return MAX_TCP_OPTION_SPACE - remaining;
@@ -751,16 +791,37 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb
size += TCPOLEN_TSTAMP_ALIGNED;
}
+ /* MPTCP options have precedence over SACK for the limited TCP
+ * option space because a MPTCP connection would be forced to
+ * fall back to regular TCP if a required multipath option is
+ * missing. SACK still gets a chance to use whatever space is
+ * left.
+ */
+ if (sk_is_mptcp(sk)) {
+ unsigned int remaining = MAX_TCP_OPTION_SPACE - size;
+ unsigned int opt_size = 0;
+
+ if (mptcp_established_options(sk, skb, &opt_size, remaining,
+ &opts->mptcp)) {
+ opts->options |= OPTION_MPTCP;
+ size += opt_size;
+ }
+ }
+
eff_sacks = tp->rx_opt.num_sacks + tp->rx_opt.dsack;
if (unlikely(eff_sacks)) {
const unsigned int remaining = MAX_TCP_OPTION_SPACE - size;
+ if (unlikely(remaining < TCPOLEN_SACK_BASE_ALIGNED +
+ TCPOLEN_SACK_PERBLOCK))
+ return size;
+
opts->num_sack_blocks =
min_t(unsigned int, eff_sacks,
(remaining - TCPOLEN_SACK_BASE_ALIGNED) /
TCPOLEN_SACK_PERBLOCK);
- if (likely(opts->num_sack_blocks))
- size += TCPOLEN_SACK_BASE_ALIGNED +
- opts->num_sack_blocks * TCPOLEN_SACK_PERBLOCK;
+
+ size += TCPOLEN_SACK_BASE_ALIGNED +
+ opts->num_sack_blocks * TCPOLEN_SACK_PERBLOCK;
}
return size;
@@ -2865,7 +2926,7 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *to,
if (!tcp_can_collapse(sk, skb))
break;
- if (!tcp_skb_can_collapse_to(to))
+ if (!tcp_skb_can_collapse(to, skb))
break;
space -= skb->len;
@@ -3369,8 +3430,8 @@ static void tcp_ca_dst_init(struct sock *sk, const struct dst_entry *dst)
rcu_read_lock();
ca = tcp_ca_find_key(ca_key);
- if (likely(ca && try_module_get(ca->owner))) {
- module_put(icsk->icsk_ca_ops->owner);
+ if (likely(ca && bpf_try_module_get(ca, ca->owner))) {
+ bpf_module_put(icsk->icsk_ca_ops, icsk->icsk_ca_ops->owner);
icsk->icsk_ca_dst_locked = tcp_ca_dst_locked(dst);
icsk->icsk_ca_ops = ca;
}