diff mbox series

[v3,net-next,4/4] net: dsa: tag_dsa: Support reception of packets from LAG devices

Message ID 20201202091356.24075-5-tobias@waldekranz.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series net: dsa: Link aggregation support | expand

Checks

Context Check Description
netdev/cover_letter success Link
netdev/fixes_present success Link
netdev/patch_count success Link
netdev/tree_selection success Clearly marked for net-next
netdev/subject_prefix success Link
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 57 lines checked
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/header_inline success Link
netdev/stable success Stable not CCed

Commit Message

Tobias Waldekranz Dec. 2, 2020, 9:13 a.m. UTC
Packets ingressing on a LAG that egress on the CPU port, which are not
classified as management, will have a FORWARD tag that does not
contain the normal source device/port tuple. Instead the trunk bit
will be set, and the port field holds the LAG id.

Since the exact source port information is not available in the tag,
frames are injected directly on the LAG interface and thus do never
pass through any DSA port interface on ingress.

Management frames (TO_CPU) are not affected and will pass through the
DSA port interface as usual.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
---
 net/dsa/dsa.c     | 12 +++++++++++-
 net/dsa/tag_dsa.c | 17 ++++++++++++++++-
 2 files changed, 27 insertions(+), 2 deletions(-)

Comments

Florian Fainelli Dec. 4, 2020, 3:58 a.m. UTC | #1
On 12/2/2020 1:13 AM, Tobias Waldekranz wrote:
> Packets ingressing on a LAG that egress on the CPU port, which are not
> classified as management, will have a FORWARD tag that does not
> contain the normal source device/port tuple. Instead the trunk bit
> will be set, and the port field holds the LAG id.
> 
> Since the exact source port information is not available in the tag,
> frames are injected directly on the LAG interface and thus do never
> pass through any DSA port interface on ingress.
> 
> Management frames (TO_CPU) are not affected and will pass through the
> DSA port interface as usual.
> 
> Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
diff mbox series

Patch

diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index a1b1dc8a4d87..7325bf4608e9 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -219,11 +219,21 @@  static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
 	}
 
 	skb = nskb;
-	p = netdev_priv(skb->dev);
 	skb_push(skb, ETH_HLEN);
 	skb->pkt_type = PACKET_HOST;
 	skb->protocol = eth_type_trans(skb, skb->dev);
 
+	if (unlikely(!dsa_slave_dev_check(skb->dev))) {
+		/* Packet is to be injected directly on an upper
+		 * device, e.g. a team/bond, so skip all DSA-port
+		 * specific actions.
+		 */
+		netif_rx(skb);
+		return 0;
+	}
+
+	p = netdev_priv(skb->dev);
+
 	if (unlikely(cpu_dp->ds->untag_bridge_pvid)) {
 		nskb = dsa_untag_bridge_pvid(skb);
 		if (!nskb) {
diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c
index 112c7c6dd568..be7271de8d0b 100644
--- a/net/dsa/tag_dsa.c
+++ b/net/dsa/tag_dsa.c
@@ -163,6 +163,7 @@  static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
 				  u8 extra)
 {
 	int source_device, source_port;
+	bool trunk = false;
 	enum dsa_code code;
 	enum dsa_cmd cmd;
 	u8 *dsa_header;
@@ -174,6 +175,8 @@  static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
 	switch (cmd) {
 	case DSA_CMD_FORWARD:
 		skb->offload_fwd_mark = 1;
+
+		trunk = !!(dsa_header[1] & 7);
 		break;
 
 	case DSA_CMD_TO_CPU:
@@ -216,7 +219,19 @@  static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
 	source_device = dsa_header[0] & 0x1f;
 	source_port = (dsa_header[1] >> 3) & 0x1f;
 
-	skb->dev = dsa_master_find_slave(dev, source_device, source_port);
+	if (trunk) {
+		struct dsa_port *cpu_dp = dev->dsa_ptr;
+
+		/* The exact source port is not available in the tag,
+		 * so we inject the frame directly on the upper
+		 * team/bond.
+		 */
+		skb->dev = dsa_lag_dev_by_id(cpu_dp->dst, source_port);
+	} else {
+		skb->dev = dsa_master_find_slave(dev, source_device,
+						 source_port);
+	}
+
 	if (!skb->dev)
 		return NULL;