[PATCH net-next v7 09/16] net: dsa: tag_sja1105: absorb entire sja1105_vlan_rcv() into dsa_8021q_rcv()

From: Pawel Dembicki
Date: Mon Mar 25 2024 - 16:47:58 EST


From: Vladimir Oltean <vladimir.oltean@xxxxxxx>

tag_sja1105 has a wrapper over dsa_8021q_rcv(): sja1105_vlan_rcv(),
which determines whether the packet came from a bridge with
vlan_filtering=1 (the case resolved via
dsa_find_designated_bridge_port_by_vid()), or if it contains a tag_8021q
header.

Looking at a new tagger implementation for vsc73xx, based also on
tag_8021q, it is becoming clear that the logic is needed there as well.
So instead of forcing each tagger to wrap around dsa_8021q_rcv(), let's
merge the logic into the core.

Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Signed-off-by: Pawel Dembicki <paweldembicki@xxxxxxxxx>
---
v7, v6:
- resend only
v5:
- add missing SoB
v4:
- introduced patch

net/dsa/tag_8021q.c | 34 ++++++++++++++++++++++++++++------
net/dsa/tag_8021q.h | 2 +-
net/dsa/tag_ocelot_8021q.c | 2 +-
net/dsa/tag_sja1105.c | 32 ++++----------------------------
4 files changed, 34 insertions(+), 36 deletions(-)

diff --git a/net/dsa/tag_8021q.c b/net/dsa/tag_8021q.c
index 3cb0293793a5..332b0ae02645 100644
--- a/net/dsa/tag_8021q.c
+++ b/net/dsa/tag_8021q.c
@@ -507,27 +507,39 @@ EXPORT_SYMBOL_GPL(dsa_tag_8021q_find_port_by_vbid);
* @vbid: pointer to storage for imprecise bridge ID. Must be pre-initialized
* with -1. If a positive value is returned, the source_port and switch_id
* are invalid.
+ * @vid: pointer to storage for original VID, in case tag_8021q decoding failed.
+ *
+ * If the packet has a tag_8021q header, decode it and set @source_port,
+ * @switch_id and @vbid, and strip the header. Otherwise set @vid and keep the
+ * header in the hwaccel area of the packet.
*/
void dsa_8021q_rcv(struct sk_buff *skb, int *source_port, int *switch_id,
- int *vbid)
+ int *vbid, int *vid)
{
int tmp_source_port, tmp_switch_id, tmp_vbid;
- u16 vid, tci;
+ __be16 vlan_proto;
+ u16 tmp_vid, tci;

if (skb_vlan_tag_present(skb)) {
+ vlan_proto = skb->vlan_proto;
tci = skb_vlan_tag_get(skb);
__vlan_hwaccel_clear_tag(skb);
} else {
+ struct vlan_ethhdr *hdr = vlan_eth_hdr(skb);
+
+ vlan_proto = hdr->h_vlan_proto;
skb_push_rcsum(skb, ETH_HLEN);
__skb_vlan_pop(skb, &tci);
skb_pull_rcsum(skb, ETH_HLEN);
}

- vid = tci & VLAN_VID_MASK;
+ tmp_vid = tci & VLAN_VID_MASK;
+ if (!vid_is_dsa_8021q(tmp_vid))
+ goto not_tag_8021q;

- tmp_source_port = dsa_8021q_rx_source_port(vid);
- tmp_switch_id = dsa_8021q_rx_switch_id(vid);
- tmp_vbid = dsa_tag_8021q_rx_vbid(vid);
+ tmp_source_port = dsa_8021q_rx_source_port(tmp_vid);
+ tmp_switch_id = dsa_8021q_rx_switch_id(tmp_vid);
+ tmp_vbid = dsa_tag_8021q_rx_vbid(tmp_vid);

/* Precise source port information is unknown when receiving from a
* VLAN-unaware bridging domain, and tmp_source_port and tmp_switch_id
@@ -546,5 +558,15 @@ void dsa_8021q_rcv(struct sk_buff *skb, int *source_port, int *switch_id,
*vbid = tmp_vbid;

skb->priority = (tci & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
+ return;
+
+not_tag_8021q:
+ if (vid)
+ *vid = tmp_vid;
+ if (vbid)
+ *vbid = -1;
+
+ /* Put the tag back */
+ __vlan_hwaccel_put_tag(skb, vlan_proto, tci);
}
EXPORT_SYMBOL_GPL(dsa_8021q_rcv);
diff --git a/net/dsa/tag_8021q.h b/net/dsa/tag_8021q.h
index 41f7167ac520..0c6671d7c1c2 100644
--- a/net/dsa/tag_8021q.h
+++ b/net/dsa/tag_8021q.h
@@ -14,7 +14,7 @@ struct sk_buff *dsa_8021q_xmit(struct sk_buff *skb, struct net_device *netdev,
u16 tpid, u16 tci);

void dsa_8021q_rcv(struct sk_buff *skb, int *source_port, int *switch_id,
- int *vbid);
+ int *vbid, int *vid);

struct net_device *dsa_tag_8021q_find_port_by_vbid(struct net_device *conduit,
int vbid);
diff --git a/net/dsa/tag_ocelot_8021q.c b/net/dsa/tag_ocelot_8021q.c
index b059381310fe..8e8b1bef6af6 100644
--- a/net/dsa/tag_ocelot_8021q.c
+++ b/net/dsa/tag_ocelot_8021q.c
@@ -81,7 +81,7 @@ static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
{
int src_port, switch_id;

- dsa_8021q_rcv(skb, &src_port, &switch_id, NULL);
+ dsa_8021q_rcv(skb, &src_port, &switch_id, NULL, NULL);

skb->dev = dsa_conduit_find_user(netdev, switch_id, src_port);
if (!skb->dev)
diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
index 48886d4b7e3e..7639ccb94d35 100644
--- a/net/dsa/tag_sja1105.c
+++ b/net/dsa/tag_sja1105.c
@@ -472,37 +472,14 @@ static bool sja1110_skb_has_inband_control_extension(const struct sk_buff *skb)
return ntohs(eth_hdr(skb)->h_proto) == ETH_P_SJA1110;
}

-/* If the VLAN in the packet is a tag_8021q one, set @source_port and
- * @switch_id and strip the header. Otherwise set @vid and keep it in the
- * packet.
- */
-static void sja1105_vlan_rcv(struct sk_buff *skb, int *source_port,
- int *switch_id, int *vbid, u16 *vid)
-{
- struct vlan_ethhdr *hdr = vlan_eth_hdr(skb);
- u16 vlan_tci;
-
- if (skb_vlan_tag_present(skb))
- vlan_tci = skb_vlan_tag_get(skb);
- else
- vlan_tci = ntohs(hdr->h_vlan_TCI);
-
- if (vid_is_dsa_8021q(vlan_tci & VLAN_VID_MASK))
- return dsa_8021q_rcv(skb, source_port, switch_id, vbid);
-
- /* Try our best with imprecise RX */
- *vid = vlan_tci & VLAN_VID_MASK;
-}
-
static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
struct net_device *netdev)
{
- int source_port = -1, switch_id = -1, vbid = -1;
+ int source_port = -1, switch_id = -1, vbid = -1, vid = -1;
struct sja1105_meta meta = {0};
struct ethhdr *hdr;
bool is_link_local;
bool is_meta;
- u16 vid;

hdr = eth_hdr(skb);
is_link_local = sja1105_is_link_local(skb);
@@ -525,7 +502,7 @@ static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
* a tag_8021q VLAN which we have to strip
*/
if (sja1105_skb_has_tag_8021q(skb))
- sja1105_vlan_rcv(skb, &source_port, &switch_id, &vbid, &vid);
+ dsa_8021q_rcv(skb, &source_port, &switch_id, &vbid, &vid);
else if (source_port == -1 && switch_id == -1)
/* Packets with no source information have no chance of
* getting accepted, drop them straight away.
@@ -660,9 +637,8 @@ static struct sk_buff *sja1110_rcv_inband_control_extension(struct sk_buff *skb,
static struct sk_buff *sja1110_rcv(struct sk_buff *skb,
struct net_device *netdev)
{
- int source_port = -1, switch_id = -1, vbid = -1;
+ int source_port = -1, switch_id = -1, vbid = -1, vid = -1;
bool host_only = false;
- u16 vid = 0;

if (sja1110_skb_has_inband_control_extension(skb)) {
skb = sja1110_rcv_inband_control_extension(skb, &source_port,
@@ -674,7 +650,7 @@ static struct sk_buff *sja1110_rcv(struct sk_buff *skb,

/* Packets with in-band control extensions might still have RX VLANs */
if (likely(sja1105_skb_has_tag_8021q(skb)))
- sja1105_vlan_rcv(skb, &source_port, &switch_id, &vbid, &vid);
+ dsa_8021q_rcv(skb, &source_port, &switch_id, &vbid, &vid);

if (vbid >= 1)
skb->dev = dsa_tag_8021q_find_port_by_vbid(netdev, vbid);
--
2.34.1