From: Stefan Raspl <raspl@linux.ibm.com>
Subject: net/smc: calculate write offset in RMB only once per connection
Patch-mainline: v4.18-rc1
Git-commit: 95d8d26306ee19f9ba32b6381571a72ee924a0b6
References: FATE#325694, LTC#167874, bsc#1113480

Summary:     net/smc: SMC-R MVP
Description: Add latest upstream patches to push SMC-R to the MVP level

Upstream-Description:

             net/smc: calculate write offset in RMB only once per connection

             Currently, the write offset within the RMB is calculated on each write
             operation although it is fixed for each connection. With this patch, the
             offset is calculated once and stored in a connection specific variable.

             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>

Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 net/smc/af_smc.c |    5 ++++-
 net/smc/smc.h    |    1 +
 net/smc/smc_tx.c |    2 +-
 3 files changed, 6 insertions(+), 2 deletions(-)

--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -377,10 +377,13 @@ static int smc_clnt_conf_first_link(stru
 static void smc_conn_save_peer_info(struct smc_sock *smc,
 				    struct smc_clc_msg_accept_confirm *clc)
 {
+	int bufsize = smc_uncompress_bufsize(clc->rmbe_size);
+
 	smc->conn.peer_rmbe_idx = clc->rmbe_idx;
 	smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token);
-	smc->conn.peer_rmbe_size = smc_uncompress_bufsize(clc->rmbe_size);
+	smc->conn.peer_rmbe_size = bufsize;
 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
+	smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
 }
 
 static void smc_link_save_peer_info(struct smc_link *link,
--- a/net/smc/smc.h
+++ b/net/smc/smc.h
@@ -150,6 +150,7 @@ struct smc_connection {
 	u16			tx_cdc_seq;	/* sequence # for CDC send */
 	spinlock_t		send_lock;	/* protect wr_sends */
 	struct delayed_work	tx_work;	/* retry of smc_cdc_msg_send */
+	u32			tx_off;		/* base offset in peer rmb */
 
 	struct smc_host_cdc_msg	local_rx_ctrl;	/* filled during event_handl.
 						 * .prod cf. TCP rcv_nxt
--- a/net/smc/smc_tx.c
+++ b/net/smc/smc_tx.c
@@ -260,7 +260,7 @@ static int smc_tx_rdma_write(struct smc_
 	rdma_wr.remote_addr =
 		lgr->rtokens[conn->rtoken_idx][SMC_SINGLE_LINK].dma_addr +
 		/* RMBE within RMB */
-		((conn->peer_rmbe_idx - 1) * conn->peer_rmbe_size) +
+		conn->tx_off +
 		/* offset within RMBE */
 		peer_rmbe_offset;
 	rdma_wr.rkey = lgr->rtokens[conn->rtoken_idx][SMC_SINGLE_LINK].rkey;