smc: establish new socket family

* enable smc module loading and unloading
 * register new socket family
 * basic smc socket creation and deletion
 * use backing TCP socket to run CLC (Connection Layer Control)
   handshake of SMC protocol
 * Setup for infiniband traffic is implemented in follow-on patches.
   For now fallback to TCP socket is always used.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reviewed-by: Utz Bacher <utz.bacher@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 37 insertions, 0 deletions

diff --git a/net/smc/smc.h b/net/smc/smc.h
new file mode 100644
index 0000000..fcea739
--- /dev/null
+++ b/net/smc/smc.h
@@ -0,0 +1,37 @@
+/*
+ *  Shared Memory Communications over RDMA (SMC-R) and RoCE
+ *
+ *  Definitions for the SMC module (socket related)
+ *
+ *  Copyright IBM Corp. 2016
+ *
+ *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
+ */
+#ifndef __SMC_H
+#define __SMC_H
+
+#include <linux/socket.h>
+#include <linux/types.h>
+#include <net/sock.h>
+
+#define SMCPROTO_SMC		0	/* SMC protocol */
+
+enum smc_state {		/* possible states of an SMC socket */
+	SMC_ACTIVE	= 1,
+	SMC_INIT	= 2,
+	SMC_CLOSED	= 7,
+	SMC_LISTEN	= 10,
+};
+
+struct smc_sock {				/* smc sock container */
+	struct sock		sk;
+	struct socket		*clcsock;	/* internal tcp socket */
+	bool			use_fallback;	/* fallback to tcp */
+};
+
+static inline struct smc_sock *smc_sk(const struct sock *sk)
+{
+	return (struct smc_sock *)sk;
+}
+
+#endif	/* __SMC_H */