rxrpc: Fix call timeouts

Fix the rxrpc call expiration timeouts and make them settable from
userspace.  By analogy with other rx implementations, there should be three
timeouts:

 (1) "Normal timeout"

     This is set for all calls and is triggered if we haven't received any
     packets from the peer in a while.  It is measured from the last time
     we received any packet on that call.  This is not reset by any
     connection packets (such as CHALLENGE/RESPONSE packets).

     If a service operation takes a long time, the server should generate
     PING ACKs at a duration that's substantially less than the normal
     timeout so is to keep both sides alive.  This is set at 1/6 of normal
     timeout.

 (2) "Idle timeout"

     This is set only for a service call and is triggered if we stop
     receiving the DATA packets that comprise the request data.  It is
     measured from the last time we received a DATA packet.

 (3) "Hard timeout"

     This can be set for a call and specified the maximum lifetime of that
     call.  It should not be specified by default.  Some operations (such
     as volume transfer) take a long time.

Allow userspace to set/change the timeouts on a call with sendmsg, using a
control message:

	RXRPC_SET_CALL_TIMEOUTS

The data to the message is a number of 32-bit words, not all of which need
be given:

	u32 hard_timeout;	/* sec from first packet */
	u32 idle_timeout;	/* msec from packet Rx */
	u32 normal_timeout;	/* msec from data Rx */

This can be set in combination with any other sendmsg() that affects a
call.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 29 insertions, 31 deletions

diff --git a/net/rxrpc/sysctl.c b/net/rxrpc/sysctl.c
index 34c706d2f79c..4a7af7aff37d 100644
--- a/net/rxrpc/sysctl.c
+++ b/net/rxrpc/sysctl.c
@@ -21,6 +21,8 @@ static const unsigned int four = 4;
 static const unsigned int thirtytwo = 32;
 static const unsigned int n_65535 = 65535;
 static const unsigned int n_max_acks = RXRPC_RXTX_BUFF_SIZE - 1;
+static const unsigned long one_jiffy = 1;
+static const unsigned long max_jiffies = MAX_JIFFY_OFFSET;
 
 /*
  * RxRPC operating parameters.
@@ -29,64 +31,60 @@ static const unsigned int n_max_acks = RXRPC_RXTX_BUFF_SIZE - 1;
  * information on the individual parameters.
  */
 static struct ctl_table rxrpc_sysctl_table[] = {
-	/* Values measured in milliseconds */
+	/* Values measured in milliseconds but used in jiffies */
 	{
 		.procname	= "req_ack_delay",
 		.data		= &rxrpc_requested_ack_delay,
-		.maxlen		= sizeof(unsigned int),
+		.maxlen		= sizeof(unsigned long),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-		.extra1		= (void *)&zero,
+		.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
+		.extra1		= (void *)&one_jiffy,
+		.extra2		= (void *)&max_jiffies,
 	},
 	{
 		.procname	= "soft_ack_delay",
 		.data		= &rxrpc_soft_ack_delay,
-		.maxlen		= sizeof(unsigned int),
+		.maxlen		= sizeof(unsigned long),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-		.extra1		= (void *)&one,
+		.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
+		.extra1		= (void *)&one_jiffy,
+		.extra2		= (void *)&max_jiffies,
 	},
 	{
 		.procname	= "idle_ack_delay",
 		.data		= &rxrpc_idle_ack_delay,
-		.maxlen		= sizeof(unsigned int),
+		.maxlen		= sizeof(unsigned long),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-		.extra1		= (void *)&one,
-	},
-	{
-		.procname	= "resend_timeout",
-		.data		= &rxrpc_resend_timeout,
-		.maxlen		= sizeof(unsigned int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-		.extra1		= (void *)&one,
+		.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
+		.extra1		= (void *)&one_jiffy,
+		.extra2		= (void *)&max_jiffies,
 	},
 	{
 		.procname	= "idle_conn_expiry",
 		.data		= &rxrpc_conn_idle_client_expiry,
-		.maxlen		= sizeof(unsigned int),
+		.maxlen		= sizeof(unsigned long),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec_ms_jiffies,
-		.extra1		= (void *)&one,
+		.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
+		.extra1		= (void *)&one_jiffy,
+		.extra2		= (void *)&max_jiffies,
 	},
 	{
 		.procname	= "idle_conn_fast_expiry",
 		.data		= &rxrpc_conn_idle_client_fast_expiry,
-		.maxlen		= sizeof(unsigned int),
+		.maxlen		= sizeof(unsigned long),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec_ms_jiffies,
-		.extra1		= (void *)&one,
+		.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
+		.extra1		= (void *)&one_jiffy,
+		.extra2		= (void *)&max_jiffies,
 	},
-
-	/* Values measured in seconds but used in jiffies */
 	{
-		.procname	= "max_call_lifetime",
-		.data		= &rxrpc_max_call_lifetime,
-		.maxlen		= sizeof(unsigned int),
+		.procname	= "resend_timeout",
+		.data		= &rxrpc_resend_timeout,
+		.maxlen		= sizeof(unsigned long),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-		.extra1		= (void *)&one,
+		.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
+		.extra1		= (void *)&one_jiffy,
+		.extra2		= (void *)&max_jiffies,
 	},
 
 	/* Non-time values */