From: Boris Pismenny <borisp@mellanox.com>
Date: Fri, 13 Jul 2018 14:33:42 +0300
Subject: tls: Fill software context without allocation
Patch-mainline: v4.19-rc1
Git-commit: b190a587c634a8559e4ceabeb0468e93db49789a
References: bsc#1109837

This patch allows tls_set_sw_offload to fill the context in case it was
already allocated previously.

We will use it in TLS_DEVICE to fill the RX software context.

Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/tls/tls_sw.c |   34 ++++++++++++++++++++++------------
 1 file changed, 22 insertions(+), 12 deletions(-)

--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -1089,28 +1089,38 @@ int tls_set_sw_offload(struct sock *sk,
 	}
 
 	if (tx) {
-		sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL);
-		if (!sw_ctx_tx) {
-			rc = -ENOMEM;
-			goto out;
+		if (!ctx->priv_ctx_tx) {
+			sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL);
+			if (!sw_ctx_tx) {
+				rc = -ENOMEM;
+				goto out;
+			}
+			ctx->priv_ctx_tx = sw_ctx_tx;
+		} else {
+			sw_ctx_tx =
+				(struct tls_sw_context_tx *)ctx->priv_ctx_tx;
 		}
-		crypto_init_wait(&sw_ctx_tx->async_wait);
-		ctx->priv_ctx_tx = sw_ctx_tx;
 	} else {
-		sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL);
-		if (!sw_ctx_rx) {
-			rc = -ENOMEM;
-			goto out;
+		if (!ctx->priv_ctx_rx) {
+			sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL);
+			if (!sw_ctx_rx) {
+				rc = -ENOMEM;
+				goto out;
+			}
+			ctx->priv_ctx_rx = sw_ctx_rx;
+		} else {
+			sw_ctx_rx =
+				(struct tls_sw_context_rx *)ctx->priv_ctx_rx;
 		}
-		crypto_init_wait(&sw_ctx_rx->async_wait);
-		ctx->priv_ctx_rx = sw_ctx_rx;
 	}
 
 	if (tx) {
+		crypto_init_wait(&sw_ctx_tx->async_wait);
 		crypto_info = &ctx->crypto_send;
 		cctx = &ctx->tx;
 		aead = &sw_ctx_tx->aead_send;
 	} else {
+		crypto_init_wait(&sw_ctx_rx->async_wait);
 		crypto_info = &ctx->crypto_recv;
 		cctx = &ctx->rx;
 		aead = &sw_ctx_rx->aead_recv;