mptcp: better binary layout for mptcp_options_received

This change reorder the mptcp_options_received fields
to shrink the structure a bit and to ensure the most
frequently used fields are all in the first cacheline.

Sub-opt specific flags are moved out of the suboptions area,
and we must now explicitly set them when the relevant
suboption is parsed.

There is a notable exception: 'csum_reqd' is used by both DSS
and MPC suboptions, and keeping such field in the suboptions
flag area will simplfy the next patch.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index f012a71..79b68ae 100644 (file)
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -83,8 +83,7 @@ static void mptcp_parse_option(const struct sk_buff *skb,
                if (flags & MPTCP_CAP_CHECKSUM_REQD)
                        mp_opt->csum_reqd = 1;
 
-               if (flags & MPTCP_CAP_DENY_JOIN_ID0)
-                       mp_opt->deny_join_id0 = 1;
+               mp_opt->deny_join_id0 = !!(flags & MPTCP_CAP_DENY_JOIN_ID0);
 
                mp_opt->mp_capable = 1;
                if (opsize >= TCPOLEN_MPTCP_MPC_SYNACK) {
@@ -262,6 +261,8 @@ static void mptcp_parse_option(const struct sk_buff *skb,
 
                mp_opt->add_addr = 1;
                mp_opt->addr.id = *ptr++;
+               mp_opt->addr.port = 0;
+               mp_opt->ahmac = 0;
                if (mp_opt->addr.family == AF_INET) {
                        memcpy((u8 *)&mp_opt->addr.addr.s_addr, (u8 *)ptr, 4);
                        ptr += 4;
@@ -363,15 +364,12 @@ void mptcp_get_options(const struct sock *sk,
        mp_opt->mp_capable = 0;
        mp_opt->mp_join = 0;
        mp_opt->add_addr = 0;
-       mp_opt->ahmac = 0;
        mp_opt->fastclose = 0;
-       mp_opt->addr.port = 0;
        mp_opt->rm_addr = 0;
        mp_opt->dss = 0;
        mp_opt->mp_prio = 0;
        mp_opt->reset = 0;
        mp_opt->csum_reqd = 0;
-       mp_opt->deny_join_id0 = 0;
        mp_opt->mp_fail = 0;
 
        length = (th->doff * 4) - sizeof(struct tcphdr);

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 57a50b1..9a0d91f 100644 (file)
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -140,28 +140,28 @@ struct mptcp_options_received {
                add_addr : 1,
                rm_addr : 1,
                mp_prio : 1,
-               mp_fail : 1,
-               echo : 1,
                csum_reqd : 1,
-               backup : 1,
-               deny_join_id0 : 1;
+               mp_fail : 1;
        u32     token;
        u32     nonce;
-       u64     thmac;
-       u8      hmac[MPTCPOPT_HMAC_LEN];
-       u8      join_id;
-       u8      use_map:1,
+       u16     use_map:1,
                dsn64:1,
                data_fin:1,
                use_ack:1,
                ack64:1,
                mpc_map:1,
+               reset_reason:4,
+               reset_transient:1,
+               echo:1,
+               backup:1,
+               deny_join_id0:1,
                __unused:2;
+       u8      join_id;
+       u64     thmac;
+       u8      hmac[MPTCPOPT_HMAC_LEN];
        struct mptcp_addr_info addr;
        struct mptcp_rm_list rm_list;
        u64     ahmac;
-       u8      reset_reason:4;
-       u8      reset_transient:1;
        u64     fail_seq;
 };