[net-next 1/1] tipc: sockopt(TIPC_SO_RCVBUF) for setting receive buffer

[Jon Maloy <jon.maloy@ericsson.com>]

From: Hoang Le <hoang.h.le@dektech.com.au>

We introduce a set/getsockopt for setting socket receive buffer per
individual socket. This has turned out to sometimes be necessary for
anycast and multicast receivers when used without flow control.

Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 include/uapi/linux/tipc.h | 1 +
 net/tipc/socket.c         | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/include/uapi/linux/tipc.h b/include/uapi/linux/tipc.h
index 14bacc7..8ce4a69 100644
--- a/include/uapi/linux/tipc.h
+++ b/include/uapi/linux/tipc.h
@@ -233,6 +233,7 @@ struct sockaddr_tipc {
 #define TIPC_MCAST_REPLICAST    134     /* Default: TIPC selects. No arg */
 #define TIPC_GROUP_JOIN         135     /* Takes struct tipc_group_req* */
 #define TIPC_GROUP_LEAVE        136     /* No argument */
+#define TIPC_SO_RCVBUF          137     /* Range tipc_rmem_min:tipc_rmem_max */
 
 /*
  * Flag values
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 8b04e60..cfd519b 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -2829,6 +2829,7 @@ static int tipc_setsockopt(struct socket *sock, int lvl, int opt,
 	case TIPC_SRC_DROPPABLE:
 	case TIPC_DEST_DROPPABLE:
 	case TIPC_CONN_TIMEOUT:
+	case TIPC_SO_RCVBUF:
 		if (ol < sizeof(value))
 			return -EINVAL;
 		if (get_user(value, (u32 __user *)ov))
@@ -2877,6 +2878,10 @@ static int tipc_setsockopt(struct socket *sock, int lvl, int opt,
 	case TIPC_GROUP_LEAVE:
 		res = tipc_sk_leave(tsk);
 		break;
+	case TIPC_SO_RCVBUF:
+		value = max_t(int, value, sysctl_tipc_rmem[0]);
+		sk->sk_rcvbuf = min_t(int, value, sysctl_tipc_rmem[2]);
+		break;
 	default:
 		res = -EINVAL;
 	}
@@ -2945,6 +2950,9 @@ static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
 			tipc_group_self(tsk->group, &seq, &scope);
 		value = seq.type;
 		break;
+	case TIPC_SO_RCVBUF:
+		value = sk->sk_rcvbuf;
+		break;
 	default:
 		res = -EINVAL;
 	}
-- 
2.1.4


------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot