net: hsr: generate supervision frame without HSR/PRP tag

For a switch to offload insertion of HSR/PRP tags, frames must not be
sent to the CPU facing switch port with a tag. Generate supervision frames
(eth type ETH_P_PRP) without HSR v1 (ETH_P_HSR)/PRP tag and rely on
create_tagged_frame which inserts it later. This will allow skipping the
tag insertion for all outgoing frames in the future which is required for
HSR v1/PRP tag insertions to be offloaded.

HSR v0 supervision frames always contain tag information so insertion of
the tag can't be offloaded. IEC 62439-3 Ed.2.0 (HSR v1) specifically
notes that this was changed since v0 to allow offloading.

Signed-off-by: George McCollister <george.mccollister@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
index ab953a1..ec6a68b 100644 (file)
--- a/net/hsr/hsr_device.c
+++ b/net/hsr/hsr_device.c
@@ -230,7 +230,7 @@ static const struct header_ops hsr_header_ops = {
        .parse   = eth_header_parse,
 };
 
-static struct sk_buff *hsr_init_skb(struct hsr_port *master, u16 proto)
+static struct sk_buff *hsr_init_skb(struct hsr_port *master)
 {
        struct hsr_priv *hsr = master->hsr;
        struct sk_buff *skb;
@@ -242,8 +242,7 @@ static struct sk_buff *hsr_init_skb(struct hsr_port *master, u16 proto)
         * being, for PRP it is a trailer and for HSR it is a
         * header
         */
-       skb = dev_alloc_skb(sizeof(struct hsr_tag) +
-                           sizeof(struct hsr_sup_tag) +
+       skb = dev_alloc_skb(sizeof(struct hsr_sup_tag) +
                            sizeof(struct hsr_sup_payload) + hlen + tlen);
 
        if (!skb)
@@ -251,10 +250,9 @@ static struct sk_buff *hsr_init_skb(struct hsr_port *master, u16 proto)
 
        skb_reserve(skb, hlen);
        skb->dev = master->dev;
-       skb->protocol = htons(proto);
        skb->priority = TC_PRIO_CONTROL;
 
-       if (dev_hard_header(skb, skb->dev, proto,
+       if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
                            hsr->sup_multicast_addr,
                            skb->dev->dev_addr, skb->len) <= 0)
                goto out;
@@ -275,12 +273,10 @@ static void send_hsr_supervision_frame(struct hsr_port *master,
 {
        struct hsr_priv *hsr = master->hsr;
        __u8 type = HSR_TLV_LIFE_CHECK;
-       struct hsr_tag *hsr_tag = NULL;
        struct hsr_sup_payload *hsr_sp;
        struct hsr_sup_tag *hsr_stag;
        unsigned long irqflags;
        struct sk_buff *skb;
-       u16 proto;
 
        *interval = msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
        if (hsr->announce_count < 3 && hsr->prot_version == 0) {
@@ -289,23 +285,12 @@ static void send_hsr_supervision_frame(struct hsr_port *master,
                hsr->announce_count++;
        }
 
-       if (!hsr->prot_version)
-               proto = ETH_P_PRP;
-       else
-               proto = ETH_P_HSR;
-
-       skb = hsr_init_skb(master, proto);
+       skb = hsr_init_skb(master);
        if (!skb) {
                WARN_ONCE(1, "HSR: Could not send supervision frame\n");
                return;
        }
 
-       if (hsr->prot_version > 0) {
-               hsr_tag = skb_put(skb, sizeof(struct hsr_tag));
-               hsr_tag->encap_proto = htons(ETH_P_PRP);
-               set_hsr_tag_LSDU_size(hsr_tag, HSR_V1_SUP_LSDUSIZE);
-       }
-
        hsr_stag = skb_put(skb, sizeof(struct hsr_sup_tag));
        set_hsr_stag_path(hsr_stag, (hsr->prot_version ? 0x0 : 0xf));
        set_hsr_stag_HSR_ver(hsr_stag, hsr->prot_version);
@@ -315,8 +300,6 @@ static void send_hsr_supervision_frame(struct hsr_port *master,
        if (hsr->prot_version > 0) {
                hsr_stag->sequence_nr = htons(hsr->sup_sequence_nr);
                hsr->sup_sequence_nr++;
-               hsr_tag->sequence_nr = htons(hsr->sequence_nr);
-               hsr->sequence_nr++;
        } else {
                hsr_stag->sequence_nr = htons(hsr->sequence_nr);
                hsr->sequence_nr++;
@@ -332,7 +315,7 @@ static void send_hsr_supervision_frame(struct hsr_port *master,
        hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload));
        ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr);
 
-       if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN))
+       if (skb_put_padto(skb, ETH_ZLEN))
                return;
 
        hsr_forward_skb(skb, master);
@@ -348,10 +331,8 @@ static void send_prp_supervision_frame(struct hsr_port *master,
        struct hsr_sup_tag *hsr_stag;
        unsigned long irqflags;
        struct sk_buff *skb;
-       struct prp_rct *rct;
-       u8 *tail;
 
-       skb = hsr_init_skb(master, ETH_P_PRP);
+       skb = hsr_init_skb(master);
        if (!skb) {
                WARN_ONCE(1, "PRP: Could not send supervision frame\n");
                return;
@@ -373,17 +354,11 @@ static void send_prp_supervision_frame(struct hsr_port *master,
        hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload));
        ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr);
 
-       if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN)) {
+       if (skb_put_padto(skb, ETH_ZLEN)) {
                spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
                return;
        }
 
-       tail = skb_tail_pointer(skb) - HSR_HLEN;
-       rct = (struct prp_rct *)tail;
-       rct->PRP_suffix = htons(ETH_P_PRP);
-       set_prp_LSDU_size(rct, HSR_V1_SUP_LSDUSIZE);
-       rct->sequence_nr = htons(hsr->sequence_nr);
-       hsr->sequence_nr++;
        spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
 
        hsr_forward_skb(skb, master);

diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c
index cadfccd..d32cd87 100644 (file)
--- a/net/hsr/hsr_forward.c
+++ b/net/hsr/hsr_forward.c
@@ -186,6 +186,7 @@ static struct sk_buff *prp_fill_rct(struct sk_buff *skb,
        set_prp_LSDU_size(trailer, lsdu_size);
        trailer->sequence_nr = htons(frame->sequence_nr);
        trailer->PRP_suffix = htons(ETH_P_PRP);
+       skb->protocol = eth_hdr(skb)->h_proto;
 
        return skb;
 }
@@ -226,6 +227,7 @@ static struct sk_buff *hsr_fill_tag(struct sk_buff *skb,
        hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
        hsr_ethhdr->ethhdr.h_proto = htons(proto_version ?
                        ETH_P_HSR : ETH_P_PRP);
+       skb->protocol = hsr_ethhdr->ethhdr.h_proto;
 
        return skb;
 }
@@ -454,7 +456,11 @@ static void handle_std_frame(struct sk_buff *skb,
 void hsr_fill_frame_info(__be16 proto, struct sk_buff *skb,
                         struct hsr_frame_info *frame)
 {
-       if (proto == htons(ETH_P_PRP) ||
+       struct hsr_port *port = frame->port_rcv;
+       struct hsr_priv *hsr = port->hsr;
+
+       /* HSRv0 supervisory frames double as a tag so treat them as tagged. */
+       if ((!hsr->prot_version && proto == htons(ETH_P_PRP)) ||
            proto == htons(ETH_P_HSR)) {
                /* HSR tagged frame :- Data or Supervision */
                frame->skb_std = NULL;