[PATCH v2 net] net: dsa: tag_ocelot: use traffic class to map priority on injected header

For Ocelot switches, the CPU injected frames have an injection header
where it can specify the QoS class of the packet and the DSA tag, now it
uses the SKB priority to set that. If a traffic class to priority
mapping is configured on the netdevice (with mqprio for example ...), it
won't be considered for CPU injected headers. This patch make the QoS
class aligned to the priority to traffic class mapping if it exists.

Fixes: 8dce89aa5f32 ("net: dsa: ocelot: add tagger for Ocelot/Felix switches")
Signed-off-by: Xiaoliang Yang <redacted>
Signed-off-by: Marouen Ghodhbane <redacted>
---
v1->v2:
 - Add fix tag and resend to net branch.

 net/dsa/tag_ocelot.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/net/dsa/tag_ocelot.c b/net/dsa/tag_ocelot.c
index de1c849a0a70..4ed74d509d6a 100644
--- a/net/dsa/tag_ocelot.c
+++ b/net/dsa/tag_ocelot.c

@@ -47,9 +47,13 @@ static void ocelot_xmit_common(struct sk_buff *skb, struct net_device *netdev,
 	void *injection;
 	__be32 *prefix;
 	u32 rew_op = 0;
+	u64 qos_class;
 
 	ocelot_xmit_get_vlan_info(skb, dp, &vlan_tci, &tag_type);
 
+	qos_class = netdev_get_num_tc(netdev) ?
+		    netdev_get_prio_tc_map(netdev, skb->priority) : skb->priority;
+
 	injection = skb_push(skb, OCELOT_TAG_LEN);
 	prefix = skb_push(skb, OCELOT_SHORT_PREFIX_LEN);
 

@@ -57,7 +61,7 @@ static void ocelot_xmit_common(struct sk_buff *skb, struct net_device *netdev,
 	memset(injection, 0, OCELOT_TAG_LEN);
 	ocelot_ifh_set_bypass(injection, 1);
 	ocelot_ifh_set_src(injection, ds->num_ports);
-	ocelot_ifh_set_qos_class(injection, skb->priority);
+	ocelot_ifh_set_qos_class(injection, qos_class);
 	ocelot_ifh_set_vlan_tci(injection, vlan_tci);
 	ocelot_ifh_set_tag_type(injection, tag_type);
 

-- 
2.17.1

Hello:

This patch was applied to netdev/net.git (master)
by Jakub Kicinski [off-list ref]:

On Thu, 23 Dec 2021 15:22:11 +0800 you wrote:

For Ocelot switches, the CPU injected frames have an injection header
where it can specify the QoS class of the packet and the DSA tag, now it
uses the SKB priority to set that. If a traffic class to priority
mapping is configured on the netdevice (with mqprio for example ...), it
won't be considered for CPU injected headers. This patch make the QoS
class aligned to the priority to traffic class mapping if it exists.

[...]

Here is the summary with links:
  - [v2,net] net: dsa: tag_ocelot: use traffic class to map priority on injected header
    https://git.kernel.org/netdev/net/c/ae2778a64724

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html