net-next: dsa: add Qualcomm tag RX/TX handler

Add support for the 2-bytes Qualcomm tag that gigabit switches such as
the QCA8337/N might insert when receiving packets, or that we need
to insert while targeting specific switch ports. The tag is inserted
directly behind the ethernet header.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
John Crispin 2016-09-15 16:26:40 +02:00 коммит произвёл David S. Miller
Родитель e5dcad290a
Коммит cafdc45c94
6 изменённых файлов: 148 добавлений и 0 удалений

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@ -26,6 +26,7 @@ enum dsa_tag_protocol {
DSA_TAG_PROTO_TRAILER,
DSA_TAG_PROTO_EDSA,
DSA_TAG_PROTO_BRCM,
DSA_TAG_PROTO_QCA,
DSA_TAG_LAST, /* MUST BE LAST */
};

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@ -38,4 +38,7 @@ config NET_DSA_TAG_EDSA
config NET_DSA_TAG_TRAILER
bool
config NET_DSA_TAG_QCA
bool
endif

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@ -7,3 +7,4 @@ dsa_core-$(CONFIG_NET_DSA_TAG_BRCM) += tag_brcm.o
dsa_core-$(CONFIG_NET_DSA_TAG_DSA) += tag_dsa.o
dsa_core-$(CONFIG_NET_DSA_TAG_EDSA) += tag_edsa.o
dsa_core-$(CONFIG_NET_DSA_TAG_TRAILER) += tag_trailer.o
dsa_core-$(CONFIG_NET_DSA_TAG_QCA) += tag_qca.o

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@ -53,6 +53,9 @@ const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {
#endif
#ifdef CONFIG_NET_DSA_TAG_BRCM
[DSA_TAG_PROTO_BRCM] = &brcm_netdev_ops,
#endif
#ifdef CONFIG_NET_DSA_TAG_QCA
[DSA_TAG_PROTO_QCA] = &qca_netdev_ops,
#endif
[DSA_TAG_PROTO_NONE] = &none_ops,
};

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@ -81,5 +81,7 @@ extern const struct dsa_device_ops trailer_netdev_ops;
/* tag_brcm.c */
extern const struct dsa_device_ops brcm_netdev_ops;
/* tag_qca.c */
extern const struct dsa_device_ops qca_netdev_ops;
#endif

138
net/dsa/tag_qca.c Normal file
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@ -0,0 +1,138 @@
/*
* Copyright (c) 2015, The Linux Foundation. All rights reserved.
*
* 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 "dsa_priv.h"
#define QCA_HDR_LEN 2
#define QCA_HDR_VERSION 0x2
#define QCA_HDR_RECV_VERSION_MASK GENMASK(15, 14)
#define QCA_HDR_RECV_VERSION_S 14
#define QCA_HDR_RECV_PRIORITY_MASK GENMASK(13, 11)
#define QCA_HDR_RECV_PRIORITY_S 11
#define QCA_HDR_RECV_TYPE_MASK GENMASK(10, 6)
#define QCA_HDR_RECV_TYPE_S 6
#define QCA_HDR_RECV_FRAME_IS_TAGGED BIT(3)
#define QCA_HDR_RECV_SOURCE_PORT_MASK GENMASK(2, 0)
#define QCA_HDR_XMIT_VERSION_MASK GENMASK(15, 14)
#define QCA_HDR_XMIT_VERSION_S 14
#define QCA_HDR_XMIT_PRIORITY_MASK GENMASK(13, 11)
#define QCA_HDR_XMIT_PRIORITY_S 11
#define QCA_HDR_XMIT_CONTROL_MASK GENMASK(10, 8)
#define QCA_HDR_XMIT_CONTROL_S 8
#define QCA_HDR_XMIT_FROM_CPU BIT(7)
#define QCA_HDR_XMIT_DP_BIT_MASK GENMASK(6, 0)
static struct sk_buff *qca_tag_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct dsa_slave_priv *p = netdev_priv(dev);
u16 *phdr, hdr;
dev->stats.tx_packets++;
dev->stats.tx_bytes += skb->len;
if (skb_cow_head(skb, 0) < 0)
goto out_free;
skb_push(skb, QCA_HDR_LEN);
memmove(skb->data, skb->data + QCA_HDR_LEN, 2 * ETH_ALEN);
phdr = (u16 *)(skb->data + 2 * ETH_ALEN);
/* Set the version field, and set destination port information */
hdr = QCA_HDR_VERSION << QCA_HDR_XMIT_VERSION_S |
QCA_HDR_XMIT_FROM_CPU |
BIT(p->port);
*phdr = htons(hdr);
return skb;
out_free:
kfree_skb(skb);
return NULL;
}
static int qca_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;
u8 ver;
int port;
__be16 *phdr, hdr;
if (unlikely(!dst))
goto out_drop;
skb = skb_unshare(skb, GFP_ATOMIC);
if (!skb)
goto out;
if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN)))
goto out_drop;
/* The QCA header is added by the switch between src addr and Ethertype
* At this point, skb->data points to ethertype so header should be
* right before
*/
phdr = (__be16 *)(skb->data - 2);
hdr = ntohs(*phdr);
/* Make sure the version is correct */
ver = (hdr & QCA_HDR_RECV_VERSION_MASK) >> QCA_HDR_RECV_VERSION_S;
if (unlikely(ver != QCA_HDR_VERSION))
goto out_drop;
/* Remove QCA tag and recalculate checksum */
skb_pull_rcsum(skb, QCA_HDR_LEN);
memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - QCA_HDR_LEN,
ETH_HLEN - QCA_HDR_LEN);
/* 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 & QCA_HDR_RECV_SOURCE_PORT_MASK);
if (!ds->ports[port].netdev)
goto out_drop;
/* Update skb & forward the frame accordingly */
skb_push(skb, ETH_HLEN);
skb->pkt_type = PACKET_HOST;
skb->dev = ds->ports[port].netdev;
skb->protocol = eth_type_trans(skb, skb->dev);
skb->dev->stats.rx_packets++;
skb->dev->stats.rx_bytes += skb->len;
netif_receive_skb(skb);
return 0;
out_drop:
kfree_skb(skb);
out:
return 0;
}
const struct dsa_device_ops qca_netdev_ops = {
.xmit = qca_tag_xmit,
.rcv = qca_tag_rcv,
};