[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 <okir@suse.de>.

 Test-plan:
 Repeated mount and unmount.  Destructive testing.  Idle timeouts.

 Signed-off-by: Chuck Lever <cel@netapp.com>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/net/sunrpc/sysctl.c b/net/sunrpc/sysctl.c
index ef483262f17f..d0c9f460e411 100644
--- 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 }
 };