net/smc: add common buffer size in send and receive buffer descriptors

In addition to the buffer references, SMC currently stores the sizes of
the receive and send buffers in each connection as separate variables.
This patch introduces a buffer length variable in the common buffer
descriptor and uses this length instead.

Signed-off-by: Hans Wippel <hwippel@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/smc/smc_rx.c

@@ -51,7 +51,7 @@ static void smc_rx_wake_up(struct sock *sk)
 static void smc_rx_update_consumer(struct smc_connection *conn,
 				   union smc_host_cursor cons, size_t len)
 {
-	smc_curs_add(conn->rmbe_size, &cons, len);
+	smc_curs_add(conn->rmb_desc->len, &cons, len);
 	smc_curs_write(&conn->local_tx_ctrl.cons, smc_curs_read(&cons, conn),
 		       conn);
 	/* send consumer cursor update if required */
@@ -288,11 +288,11 @@ copy:
 			       conn);
 		/* subsequent splice() calls pick up where previous left */
 		if (splbytes)
-			smc_curs_add(conn->rmbe_size, &cons, splbytes);
+			smc_curs_add(conn->rmb_desc->len, &cons, splbytes);
 		/* determine chunks where to read from rcvbuf */
 		/* either unwrapped case, or 1st chunk of wrapped case */
-		chunk_len = min_t(size_t,
-				  copylen, conn->rmbe_size - cons.count);
+		chunk_len = min_t(size_t, copylen, conn->rmb_desc->len -
+				  cons.count);
 		chunk_len_sum = chunk_len;
 		chunk_off = cons.count;
 		smc_rmb_sync_sg_for_cpu(conn);
@@ -331,7 +331,7 @@ copy:
 			/* increased in recv tasklet smc_cdc_msg_rcv() */
 			smp_mb__before_atomic();
 			atomic_sub(copylen, &conn->bytes_to_rcv);
-			/* guarantee 0 <= bytes_to_rcv <= rmbe_size */
+			/* guarantee 0 <= bytes_to_rcv <= rmb_desc->len */
 			smp_mb__after_atomic();
 			if (msg)
 				smc_rx_update_consumer(conn, cons, copylen);