net: dsa: don't set skb->offload_fwd_mark when not offloading the bridge

DSA has gained the recent ability to deal gracefully with upper
interfaces it cannot offload, such as the bridge, bonding or team
drivers. When such uppers exist, the ports are still in standalone mode
as far as the hardware is concerned.

But when we deliver packets to the software bridge in order for that to
do the forwarding, there is an unpleasant surprise in that the bridge
will refuse to forward them. This is because we unconditionally set
skb->offload_fwd_mark = true, meaning that the bridge thinks the frames
were already forwarded in hardware by us.

Since dp->bridge_dev is populated only when there is hardware offload
for it, but not in the software fallback case, let's introduce a new
helper that can be called from the tagger data path which sets the
skb->offload_fwd_mark accordingly to zero when there is no hardware
offload for bridging. This lets the bridge forward packets back to other
interfaces of our switch, if needed.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index da3ad02d6cebdee7991ed2f55a598f22743fe1c4..e43c5dc04282dcaec963d8aa41d4cc0cce7fb229 100644 (file)
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -440,6 +440,20 @@ dsa_find_designated_bridge_port_by_vid(struct net_device *master, u16 vid)
        return NULL;
 }
 
+/* If the ingress port offloads the bridge, we mark the frame as autonomously
+ * forwarded by hardware, so the software bridge doesn't forward in twice, back
+ * to us, because we already did. However, if we're in fallback mode and we do
+ * software bridging, we are not offloading it, therefore the dp->bridge_dev
+ * pointer is not populated, and flooding needs to be done by software (we are
+ * effectively operating in standalone ports mode).
+ */
+static inline void dsa_default_offload_fwd_mark(struct sk_buff *skb)
+{
+       struct dsa_port *dp = dsa_slave_to_port(skb->dev);
+
+       skb->offload_fwd_mark = !!(dp->bridge_dev);
+}
+
 /* switch.c */
 int dsa_switch_register_notifier(struct dsa_switch *ds);
 void dsa_switch_unregister_notifier(struct dsa_switch *ds);

diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
index 0750af951fc92c88229d97fe534de55ed5de14f2..a27f5096777aab4dc03e890124ebe024fcc513e8 100644 (file)
--- a/net/dsa/tag_brcm.c
+++ b/net/dsa/tag_brcm.c
@@ -167,7 +167,7 @@ static struct sk_buff *brcm_tag_rcv_ll(struct sk_buff *skb,
        /* Remove Broadcom tag and update checksum */
        skb_pull_rcsum(skb, BRCM_TAG_LEN);
 
-       skb->offload_fwd_mark = 1;
+       dsa_default_offload_fwd_mark(skb);
 
        return skb;
 }
@@ -271,7 +271,7 @@ static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
        /* Remove Broadcom tag and update checksum */
        skb_pull_rcsum(skb, BRCM_LEG_TAG_LEN);
 
-       skb->offload_fwd_mark = 1;
+       dsa_default_offload_fwd_mark(skb);
 
        /* Move the Ethernet DA and SA */
        memmove(skb->data - ETH_HLEN,

diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c
index 0f258218c8cf813ec571896ac946094563332226..3607499d06976986114f794c63d3d9224f6cb5ad 100644 (file)
--- a/net/dsa/tag_dsa.c
+++ b/net/dsa/tag_dsa.c
@@ -198,8 +198,8 @@ static struct sk_buff *dsa_xmit_ll(struct sk_buff *skb, struct net_device *dev,
 static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
                                  u8 extra)
 {
+       bool trap = false, trunk = false;
        int source_device, source_port;
-       bool trunk = false;
        enum dsa_code code;
        enum dsa_cmd cmd;
        u8 *dsa_header;
@@ -210,8 +210,6 @@ static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
        cmd = dsa_header[0] >> 6;
        switch (cmd) {
        case DSA_CMD_FORWARD:
-               skb->offload_fwd_mark = 1;
-
                trunk = !!(dsa_header[1] & 7);
                break;
 
@@ -230,7 +228,6 @@ static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
                         * device (like a bridge) that forwarding has
                         * already been done by hardware.
                         */
-                       skb->offload_fwd_mark = 1;
                        break;
                case DSA_CODE_MGMT_TRAP:
                case DSA_CODE_IGMP_MLD_TRAP:
@@ -238,6 +235,7 @@ static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
                        /* Traps have, by definition, not been
                         * forwarded by hardware, so don't mark them.
                         */
+                       trap = true;
                        break;
                default:
                        /* Reserved code, this could be anything. Drop
@@ -271,6 +269,15 @@ static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
        if (!skb->dev)
                return NULL;
 
+       /* When using LAG offload, skb->dev is not a DSA slave interface,
+        * so we cannot call dsa_default_offload_fwd_mark and we need to
+        * special-case it.
+        */
+       if (trunk)
+               skb->offload_fwd_mark = true;
+       else if (!trap)
+               dsa_default_offload_fwd_mark(skb);
+
        /* If the 'tagged' bit is set; convert the DSA tag to a 802.1Q
         * tag, and delete the ethertype (extra) if applicable. If the
         * 'tagged' bit is cleared; delete the DSA tag, and ethertype

diff --git a/net/dsa/tag_hellcreek.c b/net/dsa/tag_hellcreek.c
index 424130f85f596d3438ce9ae616c49b4448b54115..c41208cbd9363937d02663081d5bba4aad542fa7 100644 (file)
--- a/net/dsa/tag_hellcreek.c
+++ b/net/dsa/tag_hellcreek.c
@@ -44,7 +44,7 @@ static struct sk_buff *hellcreek_rcv(struct sk_buff *skb,
 
        pskb_trim_rcsum(skb, skb->len - HELLCREEK_TAG_LEN);
 
-       skb->offload_fwd_mark = true;
+       dsa_default_offload_fwd_mark(skb);
 
        return skb;
 }

diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c
index a201ccf2435d8dee44a042351a36337309cdbff1..1c2dfa80f9b0a9b9deb6bcc5c7667b8e01f3ba76 100644 (file)
--- a/net/dsa/tag_ksz.c
+++ b/net/dsa/tag_ksz.c
@@ -24,7 +24,7 @@ static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,
 
        pskb_trim_rcsum(skb, skb->len - len);
 
-       skb->offload_fwd_mark = true;
+       dsa_default_offload_fwd_mark(skb);
 
        return skb;
 }

diff --git a/net/dsa/tag_lan9303.c b/net/dsa/tag_lan9303.c
index 26207ef39ebcf0f43f95f3fd29ed1f92f86d03cc..cf7cf2fa12402a735a2a61c967de8be33c4374d9 100644 (file)
--- a/net/dsa/tag_lan9303.c
+++ b/net/dsa/tag_lan9303.c
@@ -115,7 +115,8 @@ static struct sk_buff *lan9303_rcv(struct sk_buff *skb, struct net_device *dev,
        skb_pull_rcsum(skb, 2 + 2);
        memmove(skb->data - ETH_HLEN, skb->data - (ETH_HLEN + LAN9303_TAG_LEN),
                2 * ETH_ALEN);
-       skb->offload_fwd_mark = !(lan9303_tag1 & LAN9303_TAG_RX_TRAPPED_TO_CPU);
+       if (!(lan9303_tag1 & LAN9303_TAG_RX_TRAPPED_TO_CPU))
+               dsa_default_offload_fwd_mark(skb);
 
        return skb;
 }

diff --git a/net/dsa/tag_mtk.c b/net/dsa/tag_mtk.c
index cc3ba864ad5badf51fa4fd4297605699b2f20284..3fb80e43f3a5b543d6df402165aa8b0b49a0300c 100644 (file)
--- a/net/dsa/tag_mtk.c
+++ b/net/dsa/tag_mtk.c
@@ -92,7 +92,7 @@ static struct sk_buff *mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev,
        if (!skb->dev)
                return NULL;
 
-       skb->offload_fwd_mark = 1;
+       dsa_default_offload_fwd_mark(skb);
 
        return skb;
 }

diff --git a/net/dsa/tag_ocelot.c b/net/dsa/tag_ocelot.c
index 190f4bfd3bef646ade3bcd9df88ab2a60f64e584..3252634a29b813edd50887a9f160054bb92a916e 100644 (file)
--- a/net/dsa/tag_ocelot.c
+++ b/net/dsa/tag_ocelot.c
@@ -104,7 +104,7 @@ static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
                 */
                return NULL;
 
-       skb->offload_fwd_mark = 1;
+       dsa_default_offload_fwd_mark(skb);
        skb->priority = qos_class;
 
        /* Ocelot switches copy frames unmodified to the CPU. However, it is

diff --git a/net/dsa/tag_ocelot_8021q.c b/net/dsa/tag_ocelot_8021q.c
index d0781b05861055ee46c46933fb0440e45ad83883..c95de71d13b085efcab614995dc02b092f351a29 100644 (file)
--- a/net/dsa/tag_ocelot_8021q.c
+++ b/net/dsa/tag_ocelot_8021q.c
@@ -49,7 +49,7 @@ static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
        if (!skb->dev)
                return NULL;
 
-       skb->offload_fwd_mark = 1;
+       dsa_default_offload_fwd_mark(skb);
 
        return skb;
 }

diff --git a/net/dsa/tag_rtl4_a.c b/net/dsa/tag_rtl4_a.c
index 57c46b4ab2b3ff739f029d2b4d15df54baf4697f..f6b63aad655160b29f5cc232654b65f0807c2a17 100644 (file)
--- a/net/dsa/tag_rtl4_a.c
+++ b/net/dsa/tag_rtl4_a.c
@@ -114,7 +114,7 @@ static struct sk_buff *rtl4a_tag_rcv(struct sk_buff *skb,
                skb->data - ETH_HLEN - RTL4_A_HDR_LEN,
                2 * ETH_ALEN);
 
-       skb->offload_fwd_mark = 1;
+       dsa_default_offload_fwd_mark(skb);
 
        return skb;
 }

diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
index c1f993d592efcb7ee9bcb3d2509fbb72bf1565dc..664cb802b71a710903262b9c9c5866749f24c9ef 100644 (file)
--- a/net/dsa/tag_sja1105.c
+++ b/net/dsa/tag_sja1105.c
@@ -405,8 +405,6 @@ static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
        is_link_local = sja1105_is_link_local(skb);
        is_meta = sja1105_is_meta_frame(skb);
 
-       skb->offload_fwd_mark = 1;
-
        if (sja1105_skb_has_tag_8021q(skb)) {
                /* Normal traffic path. */
                sja1105_vlan_rcv(skb, &source_port, &switch_id, &vid);
@@ -437,6 +435,9 @@ static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
                return NULL;
        }
 
+       if (!is_link_local)
+               dsa_default_offload_fwd_mark(skb);
+
        return sja1105_rcv_meta_state_machine(skb, &meta, is_link_local,
                                              is_meta);
 }
@@ -480,7 +481,8 @@ static struct sk_buff *sja1110_rcv_meta(struct sk_buff *skb, u16 rx_header)
 
 static struct sk_buff *sja1110_rcv_inband_control_extension(struct sk_buff *skb,
                                                            int *source_port,
-                                                           int *switch_id)
+                                                           int *switch_id,
+                                                           bool *host_only)
 {
        u16 rx_header;
 
@@ -494,6 +496,9 @@ static struct sk_buff *sja1110_rcv_inband_control_extension(struct sk_buff *skb,
         */
        rx_header = ntohs(*(__be16 *)skb->data);
 
+       if (rx_header & SJA1110_RX_HEADER_HOST_ONLY)
+               *host_only = true;
+
        if (rx_header & SJA1110_RX_HEADER_IS_METADATA)
                return sja1110_rcv_meta(skb, rx_header);
 
@@ -545,13 +550,13 @@ static struct sk_buff *sja1110_rcv(struct sk_buff *skb,
                                   struct packet_type *pt)
 {
        int source_port = -1, switch_id = -1;
+       bool host_only = false;
        u16 vid;
 
-       skb->offload_fwd_mark = 1;
-
        if (sja1110_skb_has_inband_control_extension(skb)) {
                skb = sja1110_rcv_inband_control_extension(skb, &source_port,
-                                                          &switch_id);
+                                                          &switch_id,
+                                                          &host_only);
                if (!skb)
                        return NULL;
        }
@@ -569,6 +574,9 @@ static struct sk_buff *sja1110_rcv(struct sk_buff *skb,
                return NULL;
        }
 
+       if (!host_only)
+               dsa_default_offload_fwd_mark(skb);
+
        return skb;
 }
 

diff --git a/net/dsa/tag_xrs700x.c b/net/dsa/tag_xrs700x.c
index a31ff7fcb45f63bf1ef24cf184ed08a0511e9c90..da231c16ac824e9ba9e0c508b52107a20eac3375 100644 (file)
--- a/net/dsa/tag_xrs700x.c
+++ b/net/dsa/tag_xrs700x.c
@@ -46,7 +46,7 @@ static struct sk_buff *xrs700x_rcv(struct sk_buff *skb, struct net_device *dev,
                return NULL;
 
        /* Frame is forwarded by hardware, don't forward in software. */
-       skb->offload_fwd_mark = 1;
+       dsa_default_offload_fwd_mark(skb);
 
        return skb;
 }