[PATCH net-next v2 3/3] net: ethernet: rmnet: Add support for Mapv5 uplink packet

From: Sharath Chandra Vurukala
Date: Mon Feb 22 2021 - 12:00:15 EST


Adding Support for Mapv5 uplink packet.
Based on the configuration, request HW for csum offload,
by setting the csum_valid_required of Mapv5 packet.

Signed-off-by: Sharath Chandra Vurukala <sharathv@xxxxxxxxxxxxxx>
---
drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h | 4 +-
.../net/ethernet/qualcomm/rmnet/rmnet_handlers.c | 15 +++-
drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h | 8 +-
.../net/ethernet/qualcomm/rmnet/rmnet_map_data.c | 93 ++++++++++++++++++++--
include/uapi/linux/if_link.h | 1 +
5 files changed, 108 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h
index 8d8d469..8e64ca9 100644
--- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h
@@ -1,5 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0-only */
-/* Copyright (c) 2013-2014, 2016-2018 The Linux Foundation. All rights reserved.
+/* Copyright (c) 2013-2014, 2016-2018, 2021 The Linux Foundation.
+ * All rights reserved.
*
* RMNET Data configuration engine
*/
@@ -56,6 +57,7 @@ struct rmnet_priv_stats {
u64 csum_fragmented_pkt;
u64 csum_skipped;
u64 csum_sw;
+ u64 csum_hw;
};

struct rmnet_priv {
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
index 70ad6a7..e6a44cd 100644
--- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
@@ -131,26 +131,33 @@ static int rmnet_map_egress_handler(struct sk_buff *skb,
struct rmnet_port *port, u8 mux_id,
struct net_device *orig_dev)
{
- int required_headroom, additional_header_len;
+ int required_headroom, additional_header_len, csum_type;
struct rmnet_map_header *map_header;

+ csum_type = 0;
additional_header_len = 0;
required_headroom = sizeof(struct rmnet_map_header);

if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV4) {
additional_header_len = sizeof(struct rmnet_map_ul_csum_header);
required_headroom += additional_header_len;
+ csum_type = RMNET_FLAGS_EGRESS_MAP_CKSUMV4;
+ } else if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV5) {
+ additional_header_len = sizeof(struct rmnet_map_v5_csum_header);
+ csum_type = RMNET_FLAGS_EGRESS_MAP_CKSUMV5;
}

+ required_headroom += additional_header_len;
+
if (skb_headroom(skb) < required_headroom) {
if (pskb_expand_head(skb, required_headroom, 0, GFP_ATOMIC))
return -ENOMEM;
}

- if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV4)
- rmnet_map_checksum_uplink_packet(skb, orig_dev);
+ if (csum_type)
+ rmnet_map_checksum_uplink_packet(skb, port, orig_dev, csum_type);

- map_header = rmnet_map_add_map_header(skb, additional_header_len, 0);
+ map_header = rmnet_map_add_map_header(skb, additional_header_len, port, 0);
if (!map_header)
return -ENOMEM;

diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
index 2ee1ce2..84d108e 100644
--- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
@@ -64,11 +64,15 @@ enum rmnet_map_commands {
struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb,
struct rmnet_port *port);
struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb,
- int hdrlen, int pad);
+ int hdrlen,
+ struct rmnet_port *port,
+ int pad);
void rmnet_map_command(struct sk_buff *skb, struct rmnet_port *port);
int rmnet_map_checksum_downlink_packet(struct sk_buff *skb, u16 len);
void rmnet_map_checksum_uplink_packet(struct sk_buff *skb,
- struct net_device *orig_dev);
+ struct rmnet_port *port,
+ struct net_device *orig_dev,
+ int csum_type);
int rmnet_map_process_next_hdr_packet(struct sk_buff *skb, u16 len);
u8 rmnet_map_get_next_hdr_type(struct sk_buff *skb);
bool rmnet_map_get_csum_valid(struct sk_buff *skb);
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
index a3dc220..f65bdd4 100644
--- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
@@ -263,12 +263,69 @@ rmnet_map_ipv6_ul_csum_header(void *ip6hdr,
}
#endif

+static void rmnet_map_v5_checksum_uplink_packet(struct sk_buff *skb,
+ struct rmnet_port *port,
+ struct net_device *orig_dev)
+{
+ struct rmnet_priv *priv = netdev_priv(orig_dev);
+ struct rmnet_map_v5_csum_header *ul_header;
+
+ if (!(port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV5))
+ return;
+
+ ul_header = (struct rmnet_map_v5_csum_header *)
+ skb_push(skb, sizeof(*ul_header));
+ memset(ul_header, 0, sizeof(*ul_header));
+ ul_header->header_type = RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD;
+
+ if (skb->ip_summed == CHECKSUM_PARTIAL) {
+ void *iph = (char *)ul_header + sizeof(*ul_header);
+ __sum16 *check;
+ void *trans;
+ u8 proto;
+
+ if (skb->protocol == htons(ETH_P_IP)) {
+ u16 ip_len = ((struct iphdr *)iph)->ihl * 4;
+
+ proto = ((struct iphdr *)iph)->protocol;
+ trans = iph + ip_len;
+ } else if (skb->protocol == htons(ETH_P_IPV6)) {
+#if IS_ENABLED(CONFIG_IPV6)
+ u16 ip_len = sizeof(struct ipv6hdr);
+
+ proto = ((struct ipv6hdr *)iph)->nexthdr;
+ trans = iph + ip_len;
+#else
+ priv->stats.csum_err_invalid_ip_version++;
+ goto sw_csum;
+#endif /* CONFIG_IPV6 */
+ } else {
+ priv->stats.csum_err_invalid_ip_version++;
+ goto sw_csum;
+ }
+
+ check = rmnet_map_get_csum_field(proto, trans);
+ if (check) {
+ skb->ip_summed = CHECKSUM_NONE;
+ /* Ask for checksum offloading */
+ ul_header->csum_valid_required = 1;
+ priv->stats.csum_hw++;
+ return;
+ }
+ }
+
+sw_csum:
+ priv->stats.csum_sw++;
+}
+
/* Adds MAP header to front of skb->data
* Padding is calculated and set appropriately in MAP header. Mux ID is
* initialized to 0.
*/
struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb,
- int hdrlen, int pad)
+ int hdrlen,
+ struct rmnet_port *port,
+ int pad)
{
struct rmnet_map_header *map_header;
u32 padding, map_datalen;
@@ -279,6 +336,11 @@ struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb,
skb_push(skb, sizeof(struct rmnet_map_header));
memset(map_header, 0, sizeof(struct rmnet_map_header));

+ /* Set next_hdr bit for csum offload packets */
+ if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV5) {
+ map_header->next_hdr = 1;
+ }
+
if (pad == RMNET_MAP_NO_PAD_BYTES) {
map_header->pkt_len = htons(map_datalen);
return map_header;
@@ -395,11 +457,8 @@ int rmnet_map_checksum_downlink_packet(struct sk_buff *skb, u16 len)
return 0;
}

-/* Generates UL checksum meta info header for IPv4 and IPv6 over TCP and UDP
- * packets that are supported for UL checksum offload.
- */
-void rmnet_map_checksum_uplink_packet(struct sk_buff *skb,
- struct net_device *orig_dev)
+static void rmnet_map_v4_checksum_uplink_packet(struct sk_buff *skb,
+ struct net_device *orig_dev)
{
struct rmnet_priv *priv = netdev_priv(orig_dev);
struct rmnet_map_ul_csum_header *ul_header;
@@ -418,10 +477,12 @@ void rmnet_map_checksum_uplink_packet(struct sk_buff *skb,

if (skb->protocol == htons(ETH_P_IP)) {
rmnet_map_ipv4_ul_csum_header(iphdr, ul_header, skb);
+ priv->stats.csum_hw++;
return;
} else if (skb->protocol == htons(ETH_P_IPV6)) {
#if IS_ENABLED(CONFIG_IPV6)
rmnet_map_ipv6_ul_csum_header(iphdr, ul_header, skb);
+ priv->stats.csum_hw++;
return;
#else
priv->stats.csum_err_invalid_ip_version++;
@@ -457,6 +518,26 @@ bool rmnet_map_get_csum_valid(struct sk_buff *skb)
return ((struct rmnet_map_v5_csum_header *)data)->csum_valid_required;
}

+/* Generates UL checksum meta info header for IPv4 and IPv6 over TCP and UDP
+ * packets that are supported for UL checksum offload.
+ */
+void rmnet_map_checksum_uplink_packet(struct sk_buff *skb,
+ struct rmnet_port *port,
+ struct net_device *orig_dev,
+ int csum_type)
+{
+ switch (csum_type) {
+ case RMNET_FLAGS_EGRESS_MAP_CKSUMV4:
+ rmnet_map_v4_checksum_uplink_packet(skb, orig_dev);
+ break;
+ case RMNET_FLAGS_EGRESS_MAP_CKSUMV5:
+ rmnet_map_v5_checksum_uplink_packet(skb, port, orig_dev);
+ break;
+ default:
+ break;
+ }
+}
+
/* Process a MAPv5 packet header */
int rmnet_map_process_next_hdr_packet(struct sk_buff *skb,
u16 len)
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 838bd29..319865f 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -1234,6 +1234,7 @@ enum {
#define RMNET_FLAGS_INGRESS_MAP_CKSUMV4 (1U << 2)
#define RMNET_FLAGS_EGRESS_MAP_CKSUMV4 (1U << 3)
#define RMNET_FLAGS_INGRESS_MAP_CKSUMV5 (1U << 4)
+#define RMNET_FLAGS_EGRESS_MAP_CKSUMV5 (1U << 5)

enum {
IFLA_RMNET_UNSPEC,
--
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