diff options
Diffstat (limited to '')
-rw-r--r-- | net/dsa/tag_trailer.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/net/dsa/tag_trailer.c b/net/dsa/tag_trailer.c new file mode 100644 index 000000000..5749ba85c --- /dev/null +++ b/net/dsa/tag_trailer.c @@ -0,0 +1,63 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * net/dsa/tag_trailer.c - Trailer tag format handling + * Copyright (c) 2008-2009 Marvell Semiconductor + */ + +#include <linux/etherdevice.h> +#include <linux/list.h> +#include <linux/slab.h> + +#include "dsa_priv.h" + +static struct sk_buff *trailer_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct dsa_port *dp = dsa_slave_to_port(dev); + u8 *trailer; + + trailer = skb_put(skb, 4); + trailer[0] = 0x80; + trailer[1] = 1 << dp->index; + trailer[2] = 0x10; + trailer[3] = 0x00; + + return skb; +} + +static struct sk_buff *trailer_rcv(struct sk_buff *skb, struct net_device *dev) +{ + u8 *trailer; + int source_port; + + if (skb_linearize(skb)) + return NULL; + + trailer = skb_tail_pointer(skb) - 4; + if (trailer[0] != 0x80 || (trailer[1] & 0xf8) != 0x00 || + (trailer[2] & 0xef) != 0x00 || trailer[3] != 0x00) + return NULL; + + source_port = trailer[1] & 7; + + skb->dev = dsa_master_find_slave(dev, 0, source_port); + if (!skb->dev) + return NULL; + + if (pskb_trim_rcsum(skb, skb->len - 4)) + return NULL; + + return skb; +} + +static const struct dsa_device_ops trailer_netdev_ops = { + .name = "trailer", + .proto = DSA_TAG_PROTO_TRAILER, + .xmit = trailer_xmit, + .rcv = trailer_rcv, + .needed_tailroom = 4, +}; + +MODULE_LICENSE("GPL"); +MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_TRAILER); + +module_dsa_tag_driver(trailer_netdev_ops); |