[PATCH net-next 1/1] net: hsr/prp: add vlan support

[Murali Karicheri <m-karicheri2@ti.com>]

This patch add support for creating vlan interfaces
over hsr/prp interface.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
---
 net/hsr/hsr_device.c  |  4 ----
 net/hsr/hsr_forward.c | 16 +++++++++++++---
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
index ab953a1a0d6c..e1951579a3ad 100644
--- a/net/hsr/hsr_device.c
+++ b/net/hsr/hsr_device.c
@@ -477,10 +477,6 @@ void hsr_dev_setup(struct net_device *dev)
 
 	/* Prevent recursive tx locking */
 	dev->features |= NETIF_F_LLTX;
-	/* VLAN on top of HSR needs testing and probably some work on
-	 * hsr_header_create() etc.
-	 */
-	dev->features |= NETIF_F_VLAN_CHALLENGED;
 	/* Not sure about this. Taken from bridge code. netdev_features.h says
 	 * it means "Does not change network namespaces".
 	 */
diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c
index cadfccd7876e..de21df30b0d9 100644
--- a/net/hsr/hsr_forward.c
+++ b/net/hsr/hsr_forward.c
@@ -208,6 +208,7 @@ static struct sk_buff *hsr_fill_tag(struct sk_buff *skb,
 				    struct hsr_port *port, u8 proto_version)
 {
 	struct hsr_ethhdr *hsr_ethhdr;
+	unsigned char *pc;
 	int lsdu_size;
 
 	/* pad to minimum packet size which is 60 + 6 (HSR tag) */
@@ -218,7 +219,18 @@ static struct sk_buff *hsr_fill_tag(struct sk_buff *skb,
 	if (frame->is_vlan)
 		lsdu_size -= 4;
 
-	hsr_ethhdr = (struct hsr_ethhdr *)skb_mac_header(skb);
+	pc = skb_mac_header(skb);
+	if (frame->is_vlan)
+		/* This 4-byte shift (size of a vlan tag) does not
+		 * mean that the ethhdr starts there. But rather it
+		 * provides the proper environment for accessing
+		 * the fields, such as hsr_tag etc., just like
+		 * when the vlan tag is not there. This is because
+		 * the hsr tag is after the vlan tag.
+		 */
+		hsr_ethhdr = (struct hsr_ethhdr *)(pc + VLAN_HLEN);
+	else
+		hsr_ethhdr = (struct hsr_ethhdr *)pc;
 
 	hsr_set_path_id(hsr_ethhdr, port);
 	set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, lsdu_size);
@@ -511,8 +523,6 @@ static int fill_frame_info(struct hsr_frame_info *frame,
 	if (frame->is_vlan) {
 		vlan_hdr = (struct hsr_vlan_ethhdr *)ethhdr;
 		proto = vlan_hdr->vlanhdr.h_vlan_encapsulated_proto;
-		/* FIXME: */
-		netdev_warn_once(skb->dev, "VLAN not yet supported");
 	}
 
 	frame->is_from_san = false;
-- 
2.17.1