[PATCH] RPC: allow RPC client's port range to be adjustable Select an RPC client source port between 650 and 1023 instead of between 1 and 800. The old range conflicts with a number of network services. Provide sysctls to allow admins to select a different port range. Note that this doesn't affect user-level RPC library behavior, which still uses 1 to 800. Based on a suggestion by Olaf Kirch . Test-plan: Repeated mount and unmount. Destructive testing. Idle timeouts. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- include/linux/sunrpc/debug.h | 2 ++ include/linux/sunrpc/xprt.h | 17 ++++++++++++++--- net/sunrpc/sysctl.c | 29 +++++++++++++++++++++++++++++ net/sunrpc/xprtsock.c | 23 ++++++++--------------- 4 files changed, 53 insertions(+), 18 deletions(-) diff --git a/include/linux/sunrpc/debug.h b/include/linux/sunrpc/debug.h --- a/include/linux/sunrpc/debug.h +++ b/include/linux/sunrpc/debug.h @@ -95,6 +95,8 @@ enum { CTL_NLMDEBUG, CTL_SLOTTABLE_UDP, CTL_SLOTTABLE_TCP, + CTL_MIN_RESVPORT, + CTL_MAX_RESVPORT, }; #endif /* _LINUX_SUNRPC_DEBUG_H_ */ diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -52,6 +52,17 @@ extern unsigned int xprt_tcp_slot_table_ #define RPC_REPHDRSIZE 4 /* + * Parameters for choosing a free port + */ +extern unsigned int xprt_min_resvport; +extern unsigned int xprt_max_resvport; + +#define RPC_MIN_RESVPORT (1U) +#define RPC_MAX_RESVPORT (65535U) +#define RPC_DEF_MIN_RESVPORT (650U) +#define RPC_DEF_MAX_RESVPORT (1023U) + +/* * This describes a timeout strategy */ struct rpc_timeout { @@ -62,6 +73,9 @@ struct rpc_timeout { unsigned char to_exponential; }; +struct rpc_task; +struct rpc_xprt; + /* * This describes a complete RPC request */ @@ -107,9 +121,6 @@ struct rpc_rqst { #define rq_svec rq_snd_buf.head #define rq_slen rq_snd_buf.len -struct rpc_task; -struct rpc_xprt; - struct rpc_xprt_ops { void (*set_buffer_size)(struct rpc_xprt *xprt); int (*reserve_xprt)(struct rpc_task *task); diff --git a/net/sunrpc/sysctl.c b/net/sunrpc/sysctl.c --- a/net/sunrpc/sysctl.c +++ b/net/sunrpc/sysctl.c @@ -121,9 +121,16 @@ done: unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE; unsigned int xprt_tcp_slot_table_entries = RPC_DEF_SLOT_TABLE; +unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT; +EXPORT_SYMBOL(xprt_min_resvport); +unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT; +EXPORT_SYMBOL(xprt_max_resvport); + static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE; static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE; +static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT; +static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT; static ctl_table debug_table[] = { { @@ -180,6 +187,28 @@ static ctl_table debug_table[] = { .extra1 = &min_slot_table_size, .extra2 = &max_slot_table_size }, + { + .ctl_name = CTL_MIN_RESVPORT, + .procname = "min_resvport", + .data = &xprt_min_resvport, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = &proc_dointvec_minmax, + .strategy = &sysctl_intvec, + .extra1 = &xprt_min_resvport_limit, + .extra2 = &xprt_max_resvport_limit + }, + { + .ctl_name = CTL_MAX_RESVPORT, + .procname = "max_resvport", + .data = &xprt_max_resvport, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = &proc_dointvec_minmax, + .strategy = &sysctl_intvec, + .extra1 = &xprt_min_resvport_limit, + .extra2 = &xprt_max_resvport_limit + }, { .ctl_name = 0 } }; diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -36,11 +36,6 @@ #include /* - * Maximum port number to use when requesting a reserved port. - */ -#define XS_MAX_RESVPORT (800U) - -/* * How many times to try sending a request on a socket before waiting * for the socket buffer to clear. */ @@ -873,10 +868,9 @@ static int xs_bindresvport(struct rpc_xp struct sockaddr_in myaddr = { .sin_family = AF_INET, }; - int err, port; + int err; + unsigned short port = xprt->port; - /* Were we already bound to a given port? Try to reuse it */ - port = xprt->port; do { myaddr.sin_port = htons(port); err = sock->ops->bind(sock, (struct sockaddr *) &myaddr, @@ -887,8 +881,10 @@ static int xs_bindresvport(struct rpc_xp port); return 0; } - if (--port == 0) - port = XS_MAX_RESVPORT; + if (port <= xprt_min_resvport) + port = xprt_max_resvport; + else + port--; } while (err == -EADDRINUSE && port != xprt->port); dprintk("RPC: can't bind to reserved port (%d).\n", -err); @@ -1075,9 +1071,6 @@ static struct rpc_xprt_ops xs_tcp_ops = .destroy = xs_destroy, }; -extern unsigned int xprt_udp_slot_table_entries; -extern unsigned int xprt_tcp_slot_table_entries; - /** * xs_setup_udp - Set up transport to use a UDP socket * @xprt: transport to set up @@ -1098,7 +1091,7 @@ int xs_setup_udp(struct rpc_xprt *xprt, memset(xprt->slot, 0, slot_table_size); xprt->prot = IPPROTO_UDP; - xprt->port = XS_MAX_RESVPORT; + xprt->port = xprt_max_resvport; xprt->tsh_size = 0; xprt->resvport = capable(CAP_NET_BIND_SERVICE) ? 1 : 0; /* XXX: header size can vary due to auth type, IPv6, etc. */ @@ -1136,7 +1129,7 @@ int xs_setup_tcp(struct rpc_xprt *xprt, memset(xprt->slot, 0, slot_table_size); xprt->prot = IPPROTO_TCP; - xprt->port = XS_MAX_RESVPORT; + xprt->port = xprt_max_resvport; xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32); xprt->resvport = capable(CAP_NET_BIND_SERVICE) ? 1 : 0; xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;