net/hsr: Better frame dispatch

This patch removes the separate paths for frames coming from the outside, and
frames sent from the HSR device, and instead makes all frames go through
hsr_forward_skb() in hsr_forward.c. This greatly improves code readability and
also opens up the possibility for future support of the HSR Interlink device
that is the basis for HSR RedBoxes and HSR QuadBoxes, as well as VLAN
compatibility.

Other improvements:
* A reduction in the number of times an skb is copied on machines without
  HAVE_EFFICIENT_UNALIGNED_ACCESS, which improves throughput somewhat.
* Headers are now created using the standard eth_header(), and using the
  standard hard_header_len.
* Each HSR slave now gets its own private skb, so slave-specific fields can be
  correctly set.

Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 2 deletions

diff --git a/net/hsr/hsr_main.h b/net/hsr/hsr_main.h
index e31c3069fdf8..5a9c69962ded 100644
--- a/net/hsr/hsr_main.h
+++ b/net/hsr/hsr_main.h
@@ -29,6 +29,7 @@
  * each node differ before we notify of communication problem?
  */
 #define MAX_SLAVE_DIFF			 3000 /* ms */
+#define HSR_SEQNR_START			(USHRT_MAX - 1024)
 
 
 /* How often shall we check for broken ring and remove node entries older than
@@ -153,10 +154,9 @@ struct hsr_port {
 };
 
 struct hsr_priv {
-	struct list_head	hsr_list;	/* List of hsr devices */
 	struct rcu_head		rcu_head;
 	struct list_head	ports;
-	struct list_head	node_db;	/* Other HSR nodes */
+	struct list_head	node_db;	/* Known HSR nodes */
 	struct list_head	self_node_db;	/* MACs of slaves */
 	struct timer_list	announce_timer;	/* Supervision frame dispatch */
 	struct timer_list	prune_timer;
@@ -166,6 +166,18 @@ struct hsr_priv {
 	unsigned char		sup_multicast_addr[ETH_ALEN];
 };
 
+#define hsr_for_each_port(hsr, port) \
+	list_for_each_entry_rcu((port), &(hsr)->ports, port_list)
+
 struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt);
 
+/* Caller must ensure skb is a valid HSR frame */
+static inline u16 hsr_get_skb_sequence_nr(struct sk_buff *skb)
+{
+	struct hsr_ethhdr *hsr_ethhdr;
+
+	hsr_ethhdr = (struct hsr_ethhdr *) skb_mac_header(skb);
+	return ntohs(hsr_ethhdr->hsr_tag.sequence_nr);
+}
+
 #endif /*  __HSR_PRIVATE_H */