cregit-Linux how code gets into the kernel

Release 4.12 net/dsa/tag_mtk.c

Directory: net/dsa
/*
 * Mediatek DSA Tag support
 * Copyright (C) 2017 Landen Chao <landen.chao@mediatek.com>
 *                    Sean Wang <sean.wang@mediatek.com>
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/etherdevice.h>
#include <net/dsa.h>
#include "dsa_priv.h"


#define MTK_HDR_LEN		4

#define MTK_HDR_RECV_SOURCE_PORT_MASK	GENMASK(2, 0)

#define MTK_HDR_XMIT_DP_BIT_MASK	GENMASK(5, 0)


static struct sk_buff *mtk_tag_xmit(struct sk_buff *skb, struct net_device *dev) { struct dsa_slave_priv *p = netdev_priv(dev); u8 *mtk_tag; if (skb_cow_head(skb, MTK_HDR_LEN) < 0) goto out_free; skb_push(skb, MTK_HDR_LEN); memmove(skb->data, skb->data + MTK_HDR_LEN, 2 * ETH_ALEN); /* Build the tag after the MAC Source Address */ mtk_tag = skb->data + 2 * ETH_ALEN; mtk_tag[0] = 0; mtk_tag[1] = (1 << p->dp->index) & MTK_HDR_XMIT_DP_BIT_MASK; mtk_tag[2] = 0; mtk_tag[3] = 0; return skb; out_free: kfree_skb(skb); return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Sean Wang132100.00%1100.00%
Total132100.00%1100.00%


static struct sk_buff *mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { struct dsa_switch_tree *dst = dev->dsa_ptr; struct dsa_switch *ds; int port; __be16 *phdr, hdr; if (unlikely(!pskb_may_pull(skb, MTK_HDR_LEN))) goto out_drop; /* The MTK header is added by the switch between src addr * and ethertype at this point, skb->data points to 2 bytes * after src addr so header should be 2 bytes right before. */ phdr = (__be16 *)(skb->data - 2); hdr = ntohs(*phdr); /* Remove MTK tag and recalculate checksum. */ skb_pull_rcsum(skb, MTK_HDR_LEN); memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - MTK_HDR_LEN, 2 * ETH_ALEN); /* This protocol doesn't support cascading multiple * switches so it's safe to assume the switch is first * in the tree. */ ds = dst->ds[0]; if (!ds) goto out_drop; /* Get source port information */ port = (hdr & MTK_HDR_RECV_SOURCE_PORT_MASK); if (!ds->ports[port].netdev) goto out_drop; skb->dev = ds->ports[port].netdev; return skb; out_drop: return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Sean Wang17797.25%150.00%
Florian Fainelli52.75%150.00%
Total182100.00%2100.00%

const struct dsa_device_ops mtk_netdev_ops = { .xmit = mtk_tag_xmit, .rcv = mtk_tag_rcv, };

Overall Contributors

PersonTokensPropCommitsCommitProp
Sean Wang34898.58%150.00%
Florian Fainelli51.42%150.00%
Total353100.00%2100.00%
Directory: net/dsa
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.