net: rmnet_data: Add support for guaranteed padding

Added new parameter tail_spacing to
RMNET_NETLINK_SET_LINK_INGRESS_DATA_FORMAT in order to support
an additional fixed padding on packets. Required to support RNDIS
tethering.

CRs-Fixed: 579184
Change-Id: I58bbbfbaa68a28b25a96f52b04165285de9c24ef
Signed-off-by: Harout Hedeshian <harouth@codeaurora.org>

4 files changed, 17 insertions, 8 deletions

diff --git a/net/rmnet_data/rmnet_data_config.c b/net/rmnet_data/rmnet_data_config.c
index d013425d9bfa..5a92893f67b3 100644
--- a/net/rmnet_data/rmnet_data_config.c
+++ b/net/rmnet_data/rmnet_data_config.c
@@ -218,9 +218,10 @@ static void _rmnet_netlink_set_link_ingress_data_format
 		return;
 	}
 
-	resp_rmnet->return_code =
-		rmnet_set_ingress_data_format(dev,
-					      rmnet_header->data_format.flags);
+	resp_rmnet->return_code = rmnet_set_ingress_data_format(
+					dev,
+					rmnet_header->data_format.flags,
+					rmnet_header->data_format.tail_spacing);
 	dev_put(dev);
 }
 
@@ -384,6 +385,7 @@ static void _rmnet_netlink_get_link_ingress_data_format
 	resp_rmnet->crd = RMNET_NETLINK_MSG_RETURNDATA;
 	resp_rmnet->arg_length = RMNET_NL_MSG_SIZE(data_format);
 	resp_rmnet->data_format.flags = config->ingress_data_format;
+	resp_rmnet->data_format.tail_spacing = config->tail_spacing;
 	dev_put(dev);
 }
 
@@ -643,7 +645,8 @@ int rmnet_unassociate_network_device(struct net_device *dev)
  *      - RMNET_CONFIG_UNKNOWN_ERROR net_device private section is null
  */
 int rmnet_set_ingress_data_format(struct net_device *dev,
-				      uint32_t ingress_data_format)
+				  uint32_t ingress_data_format,
+				  uint8_t  tail_spacing)
 {
 	struct rmnet_phys_ep_conf_s *config;
 	ASSERT_RTNL();
@@ -659,6 +662,7 @@ int rmnet_set_ingress_data_format(struct net_device *dev,
 		return RMNET_CONFIG_INVALID_REQUEST;
 
 	config->ingress_data_format = ingress_data_format;
+	config->tail_spacing = tail_spacing;
 
 	return RMNET_CONFIG_OK;
 }
diff --git a/net/rmnet_data/rmnet_data_config.h b/net/rmnet_data/rmnet_data_config.h
index b408c4f01104..e6b5481bdcb0 100644
--- a/net/rmnet_data/rmnet_data_config.h
+++ b/net/rmnet_data/rmnet_data_config.h
@@ -43,6 +43,7 @@ struct rmnet_phys_ep_conf_s {
 	struct sk_buff *agg_skb;
 	uint8_t agg_state;
 	uint8_t agg_count;
+	uint8_t tail_spacing;
 };
 
 int rmnet_config_init(void);
@@ -50,7 +51,8 @@ void rmnet_config_exit(void);
 
 int rmnet_unassociate_network_device(struct net_device *dev);
 int rmnet_set_ingress_data_format(struct net_device *dev,
-				  uint32_t ingress_data_format);
+				  uint32_t ingress_data_format,
+				  uint8_t  tail_spacing);
 int rmnet_set_egress_data_format(struct net_device *dev,
 				 uint32_t egress_data_format,
 				 uint16_t agg_size,
diff --git a/net/rmnet_data/rmnet_data_handlers.c b/net/rmnet_data/rmnet_data_handlers.c
index 7c9a8263f144..68cfac20e80c 100644
--- a/net/rmnet_data/rmnet_data_handlers.c
+++ b/net/rmnet_data/rmnet_data_handlers.c
@@ -253,7 +253,9 @@ static rx_handler_result_t _rmnet_map_ingress_handler(struct sk_buff *skb,
 	uint16_t len;
 
 	mux_id = RMNET_MAP_GET_MUX_ID(skb);
-	len = RMNET_MAP_GET_LENGTH(skb) - RMNET_MAP_GET_PAD(skb);
+	len = RMNET_MAP_GET_LENGTH(skb)
+			- RMNET_MAP_GET_PAD(skb)
+			- config->tail_spacing;
 
 	if (mux_id >= RMNET_DATA_MAX_LOGICAL_EP) {
 		LOGD("%s(): Got packet on %s with bad mux id %d\n",
diff --git a/net/rmnet_data/rmnet_map_data.c b/net/rmnet_data/rmnet_map_data.c
index 9c8fb5d656a8..d7bda86448fb 100644
--- a/net/rmnet_data/rmnet_map_data.c
+++ b/net/rmnet_data/rmnet_map_data.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -108,12 +108,13 @@ struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb,
 
 	maph = (struct rmnet_map_header_s *) skb->data;
 	packet_len = ntohs(maph->pkt_len) + sizeof(struct rmnet_map_header_s);
+
 	if ((((int)skb->len) - ((int)packet_len)) < 0) {
 		LOGM("%s(): Got malformed packet. Dropping\n", __func__);
 		return 0;
 	}
 
-	skbn = skb_copy(skb, GFP_ATOMIC);
+	skbn = skb_clone(skb, GFP_ATOMIC);
 	if (!skbn)
 		return 0;