nfp: tls: implement the stream sync RX resync

The simple RX resync strategy controlled by the kernel does not
guarantee as good results as if the device helps by detecting
the potential record boundaries and keeping track of them.

We've called this strategy stream scan in the tls-offload doc.

Implement this strategy for the NFP. The device sends a request
for record boundary confirmation, which is then recorded in
per-TLS socket state and responded to once record is reached.
Because the device keeps track of records passing after the
request was sent the response is not as latency sensitive as
when kernel just tries to tell the device the information
about the next record.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 33 insertions, 8 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.c b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.c
index 45756648a85c..c3a763134e79 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.c
@@ -17,6 +17,30 @@ static void nfp_net_tlv_caps_reset(struct nfp_net_tlv_caps *caps)
 	caps->mbox_len = NFP_NET_CFG_MBOX_VAL_MAX_SZ;
 }
 
+static bool
+nfp_net_tls_parse_crypto_ops(struct device *dev, struct nfp_net_tlv_caps *caps,
+			     u8 __iomem *ctrl_mem, u8 __iomem *data,
+			     unsigned int length, unsigned int offset,
+			     bool rx_stream_scan)
+{
+	/* Ignore the legacy TLV if new one was already parsed */
+	if (caps->tls_resync_ss && !rx_stream_scan)
+		return true;
+
+	if (length < 32) {
+		dev_err(dev,
+			"CRYPTO OPS TLV should be at least 32B, is %dB offset:%u\n",
+			length, offset);
+		return false;
+	}
+
+	caps->crypto_ops = readl(data);
+	caps->crypto_enable_off = data - ctrl_mem + 16;
+	caps->tls_resync_ss = rx_stream_scan;
+
+	return true;
+}
+
 int nfp_net_tlv_caps_parse(struct device *dev, u8 __iomem *ctrl_mem,
 			   struct nfp_net_tlv_caps *caps)
 {
@@ -104,15 +128,10 @@ int nfp_net_tlv_caps_parse(struct device *dev, u8 __iomem *ctrl_mem,
 				caps->mbox_cmsg_types = readl(data);
 			break;
 		case NFP_NET_CFG_TLV_TYPE_CRYPTO_OPS:
-			if (length < 32) {
-				dev_err(dev,
-					"CRYPTO OPS TLV should be at least 32B, is %dB offset:%u\n",
-					length, offset);
+			if (!nfp_net_tls_parse_crypto_ops(dev, caps, ctrl_mem,
+							  data, length, offset,
+							  false))
 				return -EINVAL;
-			}
-
-			caps->crypto_ops = readl(data);
-			caps->crypto_enable_off = data - ctrl_mem + 16;
 			break;
 		case NFP_NET_CFG_TLV_TYPE_VNIC_STATS:
 			if ((data - ctrl_mem) % 8) {
@@ -123,6 +142,12 @@ int nfp_net_tlv_caps_parse(struct device *dev, u8 __iomem *ctrl_mem,
 			caps->vnic_stats_off = data - ctrl_mem;
 			caps->vnic_stats_cnt = length / 10;
 			break;
+		case NFP_NET_CFG_TLV_TYPE_CRYPTO_OPS_RX_SCAN:
+			if (!nfp_net_tls_parse_crypto_ops(dev, caps, ctrl_mem,
+							  data, length, offset,
+							  true))
+				return -EINVAL;
+			break;
 		default:
 			if (!FIELD_GET(NFP_NET_CFG_TLV_HEADER_REQUIRED, hdr))
 				break;