diff options
Diffstat (limited to 'net/rxrpc/ar-peer.c')
-rw-r--r-- | net/rxrpc/ar-peer.c | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/net/rxrpc/ar-peer.c b/net/rxrpc/ar-peer.c index d399de4a7fe2..ce08b78647ce 100644 --- a/net/rxrpc/ar-peer.c +++ b/net/rxrpc/ar-peer.c @@ -19,6 +19,7 @@ #include <net/sock.h> #include <net/af_rxrpc.h> #include <net/ip.h> +#include <net/route.h> #include "ar-internal.h" static LIST_HEAD(rxrpc_peers); @@ -28,6 +29,47 @@ static DECLARE_WAIT_QUEUE_HEAD(rxrpc_peer_wq); static void rxrpc_destroy_peer(struct work_struct *work); /* + * assess the MTU size for the network interface through which this peer is + * reached + */ +static void rxrpc_assess_MTU_size(struct rxrpc_peer *peer) +{ + struct rtable *rt; + struct flowi fl; + int ret; + + peer->if_mtu = 1500; + + memset(&fl, 0, sizeof(fl)); + + switch (peer->srx.transport.family) { + case AF_INET: + fl.oif = 0; + fl.proto = IPPROTO_UDP, + fl.nl_u.ip4_u.saddr = 0; + fl.nl_u.ip4_u.daddr = peer->srx.transport.sin.sin_addr.s_addr; + fl.nl_u.ip4_u.tos = 0; + /* assume AFS.CM talking to AFS.FS */ + fl.uli_u.ports.sport = htons(7001); + fl.uli_u.ports.dport = htons(7000); + break; + default: + BUG(); + } + + ret = ip_route_output_key(&rt, &fl); + if (ret < 0) { + kleave(" [route err %d]", ret); + return; + } + + peer->if_mtu = dst_mtu(&rt->u.dst); + dst_release(&rt->u.dst); + + kleave(" [if_mtu %u]", peer->if_mtu); +} + +/* * allocate a new peer */ static struct rxrpc_peer *rxrpc_alloc_peer(struct sockaddr_rxrpc *srx, @@ -47,7 +89,8 @@ static struct rxrpc_peer *rxrpc_alloc_peer(struct sockaddr_rxrpc *srx, peer->debug_id = atomic_inc_return(&rxrpc_debug_id); memcpy(&peer->srx, srx, sizeof(*srx)); - peer->mtu = peer->if_mtu = 65535; + rxrpc_assess_MTU_size(peer); + peer->mtu = peer->if_mtu; if (srx->transport.family == AF_INET) { peer->hdrsize = sizeof(struct iphdr); |