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, 7 insertions, 12 deletions

diff --git a/net/rxrpc/misc.c b/net/rxrpc/misc.c
index 1a2d4b112064..c1d9e7fd7448 100644
--- a/net/rxrpc/misc.c
+++ b/net/rxrpc/misc.c
@@ -21,33 +21,28 @@
 unsigned int rxrpc_max_backlog __read_mostly = 10;
 
 /*
- * Maximum lifetime of a call (in mx).
- */
-unsigned int rxrpc_max_call_lifetime = 60 * 1000;
-
-/*
  * How long to wait before scheduling ACK generation after seeing a
- * packet with RXRPC_REQUEST_ACK set (in ms).
+ * packet with RXRPC_REQUEST_ACK set (in jiffies).
  */
-unsigned int rxrpc_requested_ack_delay = 1;
+unsigned long rxrpc_requested_ack_delay = 1;
 
 /*
- * How long to wait before scheduling an ACK with subtype DELAY (in ms).
+ * How long to wait before scheduling an ACK with subtype DELAY (in jiffies).
  *
  * We use this when we've received new data packets.  If those packets aren't
  * all consumed within this time we will send a DELAY ACK if an ACK was not
  * requested to let the sender know it doesn't need to resend.
  */
-unsigned int rxrpc_soft_ack_delay = 1 * 1000;
+unsigned long rxrpc_soft_ack_delay = HZ;
 
 /*
- * How long to wait before scheduling an ACK with subtype IDLE (in ms).
+ * How long to wait before scheduling an ACK with subtype IDLE (in jiffies).
  *
  * We use this when we've consumed some previously soft-ACK'd packets when
  * further packets aren't immediately received to decide when to send an IDLE
  * ACK let the other end know that it can free up its Tx buffer space.
  */
-unsigned int rxrpc_idle_ack_delay = 0.5 * 1000;
+unsigned long rxrpc_idle_ack_delay = HZ / 2;
 
 /*
  * Receive window size in packets.  This indicates the maximum number of
@@ -75,7 +70,7 @@ unsigned int rxrpc_rx_jumbo_max = 4;
 /*
  * Time till packet resend (in milliseconds).
  */
-unsigned int rxrpc_resend_timeout = 4 * 1000;
+unsigned long rxrpc_resend_timeout = 4 * HZ;
 
 const s8 rxrpc_ack_priority[] = {
 	[0]				= 0,