1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* Copyright 2020-2021 NXP |
3 | * |
4 | * An implementation of the software-defined tag_8021q.c tagger format, which |
5 | * also preserves full functionality under a vlan_filtering bridge. It does |
6 | * this by using the TCAM engines for: |
7 | * - pushing the RX VLAN as a second, outer tag, on egress towards the CPU port |
8 | * - redirecting towards the correct front port based on TX VLAN and popping |
9 | * that on egress |
10 | */ |
11 | #include <linux/dsa/8021q.h> |
12 | #include <linux/dsa/ocelot.h> |
13 | |
14 | #include "tag.h" |
15 | #include "tag_8021q.h" |
16 | |
17 | #define OCELOT_8021Q_NAME "ocelot-8021q" |
18 | |
19 | struct ocelot_8021q_tagger_private { |
20 | struct ocelot_8021q_tagger_data data; /* Must be first */ |
21 | struct kthread_worker *xmit_worker; |
22 | }; |
23 | |
24 | static struct sk_buff *ocelot_defer_xmit(struct dsa_port *dp, |
25 | struct sk_buff *skb) |
26 | { |
27 | struct ocelot_8021q_tagger_private *priv = dp->ds->tagger_data; |
28 | struct ocelot_8021q_tagger_data *data = &priv->data; |
29 | void (*xmit_work_fn)(struct kthread_work *work); |
30 | struct felix_deferred_xmit_work *xmit_work; |
31 | struct kthread_worker *xmit_worker; |
32 | |
33 | xmit_work_fn = data->xmit_work_fn; |
34 | xmit_worker = priv->xmit_worker; |
35 | |
36 | if (!xmit_work_fn || !xmit_worker) |
37 | return NULL; |
38 | |
39 | /* PTP over IP packets need UDP checksumming. We may have inherited |
40 | * NETIF_F_HW_CSUM from the DSA conduit, but these packets are not sent |
41 | * through the DSA conduit, so calculate the checksum here. |
42 | */ |
43 | if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) |
44 | return NULL; |
45 | |
46 | xmit_work = kzalloc(size: sizeof(*xmit_work), GFP_ATOMIC); |
47 | if (!xmit_work) |
48 | return NULL; |
49 | |
50 | /* Calls felix_port_deferred_xmit in felix.c */ |
51 | kthread_init_work(&xmit_work->work, xmit_work_fn); |
52 | /* Increase refcount so the kfree_skb in dsa_user_xmit |
53 | * won't really free the packet. |
54 | */ |
55 | xmit_work->dp = dp; |
56 | xmit_work->skb = skb_get(skb); |
57 | |
58 | kthread_queue_work(worker: xmit_worker, work: &xmit_work->work); |
59 | |
60 | return NULL; |
61 | } |
62 | |
63 | static struct sk_buff *ocelot_xmit(struct sk_buff *skb, |
64 | struct net_device *netdev) |
65 | { |
66 | struct dsa_port *dp = dsa_user_to_port(dev: netdev); |
67 | u16 queue_mapping = skb_get_queue_mapping(skb); |
68 | u8 pcp = netdev_txq_to_tc(dev: netdev, txq: queue_mapping); |
69 | u16 tx_vid = dsa_tag_8021q_standalone_vid(dp); |
70 | struct ethhdr *hdr = eth_hdr(skb); |
71 | |
72 | if (ocelot_ptp_rew_op(skb) || is_link_local_ether_addr(addr: hdr->h_dest)) |
73 | return ocelot_defer_xmit(dp, skb); |
74 | |
75 | return dsa_8021q_xmit(skb, netdev, ETH_P_8021Q, |
76 | tci: ((pcp << VLAN_PRIO_SHIFT) | tx_vid)); |
77 | } |
78 | |
79 | static struct sk_buff *ocelot_rcv(struct sk_buff *skb, |
80 | struct net_device *netdev) |
81 | { |
82 | int src_port, switch_id; |
83 | |
84 | dsa_8021q_rcv(skb, source_port: &src_port, switch_id: &switch_id, NULL); |
85 | |
86 | skb->dev = dsa_conduit_find_user(dev: netdev, device: switch_id, port: src_port); |
87 | if (!skb->dev) |
88 | return NULL; |
89 | |
90 | dsa_default_offload_fwd_mark(skb); |
91 | |
92 | return skb; |
93 | } |
94 | |
95 | static void ocelot_disconnect(struct dsa_switch *ds) |
96 | { |
97 | struct ocelot_8021q_tagger_private *priv = ds->tagger_data; |
98 | |
99 | kthread_destroy_worker(worker: priv->xmit_worker); |
100 | kfree(objp: priv); |
101 | ds->tagger_data = NULL; |
102 | } |
103 | |
104 | static int ocelot_connect(struct dsa_switch *ds) |
105 | { |
106 | struct ocelot_8021q_tagger_private *priv; |
107 | int err; |
108 | |
109 | priv = kzalloc(size: sizeof(*priv), GFP_KERNEL); |
110 | if (!priv) |
111 | return -ENOMEM; |
112 | |
113 | priv->xmit_worker = kthread_create_worker(flags: 0, namefmt: "felix_xmit" ); |
114 | if (IS_ERR(ptr: priv->xmit_worker)) { |
115 | err = PTR_ERR(ptr: priv->xmit_worker); |
116 | kfree(objp: priv); |
117 | return err; |
118 | } |
119 | |
120 | ds->tagger_data = priv; |
121 | |
122 | return 0; |
123 | } |
124 | |
125 | static const struct dsa_device_ops ocelot_8021q_netdev_ops = { |
126 | .name = OCELOT_8021Q_NAME, |
127 | .proto = DSA_TAG_PROTO_OCELOT_8021Q, |
128 | .xmit = ocelot_xmit, |
129 | .rcv = ocelot_rcv, |
130 | .connect = ocelot_connect, |
131 | .disconnect = ocelot_disconnect, |
132 | .needed_headroom = VLAN_HLEN, |
133 | .promisc_on_conduit = true, |
134 | }; |
135 | |
136 | MODULE_DESCRIPTION("DSA tag driver for Ocelot family of switches, using VLAN" ); |
137 | MODULE_LICENSE("GPL v2" ); |
138 | MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT_8021Q, OCELOT_8021Q_NAME); |
139 | |
140 | module_dsa_tag_driver(ocelot_8021q_netdev_ops); |
141 | |