11 files changed, 258 insertions, 7 deletions

diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h
index 2140aacb6338..32b9dcda68c7 100644
--- a/include/linux/if_ether.h
+++ b/include/linux/if_ether.h
@@ -101,6 +101,7 @@
 #define ETH_P_ECONET    0x0018          /* Acorn Econet                 */
 #define ETH_P_HDLC      0x0019          /* HDLC frames                  */
 #define ETH_P_ARCNET    0x001A          /* 1A for ArcNet :-)            */
+#define ETH_P_DSA       0x001B          /* Distributed Switch Arch.     */
 #define ETH_P_PHONET    0x00F5          /* Nokia Phonet frames          */
 
 /*
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 794eeb4b3462..97f0c64c152a 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -42,6 +42,7 @@
 #include <linux/workqueue.h>
 
 #include <net/net_namespace.h>
+#include <net/dsa.h>
 
 struct vlan_group;
 struct ethtool_ops;
@@ -801,6 +802,16 @@ void dev_net_set(struct net_device *dev, struct net *net)
 #endif
 }
 
+static inline bool netdev_uses_dsa_tags(struct net_device *dev)
+{
+#ifdef CONFIG_NET_DSA_TAG_DSA
+        if (dev->dsa_ptr != NULL)
+                return dsa_uses_dsa_tags(dev->dsa_ptr);
+#endif
+
+        return 0;
+}
+
 /**
  *      netdev_priv - access network device private data
  *      @dev: network device
diff --git a/include/net/dsa.h b/include/net/dsa.h
index dc4784f54520..72e509b6a12e 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -30,5 +30,7 @@ struct dsa_platform_data {
         char            *port_names[DSA_MAX_PORTS];
 };
 
+extern bool dsa_uses_dsa_tags(void *dsa_ptr);
+
 
 #endif
diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
index 7cf55e5eb39f..6b68016827da 100644
--- a/net/dsa/Kconfig
+++ b/net/dsa/Kconfig
@@ -10,6 +10,10 @@ menuconfig NET_DSA
 if NET_DSA
 
 # tagging formats
+config NET_DSA_TAG_DSA
+        bool
+        default n
+
 config NET_DSA_TAG_EDSA
         bool
         default n
diff --git a/net/dsa/Makefile b/net/dsa/Makefile
index b59a6f6bcf56..8b92123315b8 100644
--- a/net/dsa/Makefile
+++ b/net/dsa/Makefile
@@ -1,4 +1,5 @@
 # tagging formats
+obj-$(CONFIG_NET_DSA_TAG_DSA) += tag_dsa.o
 obj-$(CONFIG_NET_DSA_TAG_EDSA) += tag_edsa.o
 
 # switch drivers
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 6cc5be2ec7f1..f8c549281c30 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -202,6 +202,22 @@ static void dsa_switch_destroy(struct dsa_switch *ds)
 }
 
 
+/* hooks for ethertype-less tagging formats *********************************/
+/*
+ * The original DSA tag format and some other tag formats have no
+ * ethertype, which means that we need to add a little hack to the
+ * networking receive path to make sure that received frames get
+ * the right ->protocol assigned to them when one of those tag
+ * formats is in use.
+ */
+bool dsa_uses_dsa_tags(void *dsa_ptr)
+{
+        struct dsa_switch *ds = dsa_ptr;
+
+        return !!(ds->tag_protocol == htons(ETH_P_DSA));
+}
+
+
 /* link polling *************************************************************/
 static void dsa_link_poll_work(struct work_struct *ugly)
 {
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 21ee9052079a..2f1d68c495e8 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -103,6 +103,9 @@ struct net_device *dsa_slave_create(struct dsa_switch *ds,
                                     struct device *parent,
                                     int port, char *name);
 
+/* tag_dsa.c */
+int dsa_xmit(struct sk_buff *skb, struct net_device *dev);
+
 /* tag_edsa.c */
 int edsa_xmit(struct sk_buff *skb, struct net_device *dev);
 
diff --git a/net/dsa/mv88e6123_61_65.c b/net/dsa/mv88e6123_61_65.c
index 147818cc706e..555b164082fc 100644
--- a/net/dsa/mv88e6123_61_65.c
+++ b/net/dsa/mv88e6123_61_65.c
@@ -192,15 +192,19 @@ static int mv88e6123_61_65_setup_port(struct dsa_switch *ds, int p)
 
         /*
          * Port Control: disable Drop-on-Unlock, disable Drop-on-Lock,
-         * configure the EDSA tagging mode if this is the CPU port,
-         * disable Header mode, enable IGMP/MLD snooping, disable VLAN
-         * tunneling, determine priority by looking at 802.1p and IP
-         * priority fields (IP prio has precedence), and set STP state
-         * to Forwarding.  Finally, if this is the CPU port, additionally
-         * enable forwarding of unknown unicast and multicast addresses.
+         * configure the requested (DSA/EDSA) tagging mode if this is
+         * the CPU port, disable Header mode, enable IGMP/MLD snooping,
+         * disable VLAN tunneling, determine priority by looking at
+         * 802.1p and IP priority fields (IP prio has precedence), and
+         * set STP state to Forwarding.  Finally, if this is the CPU
+         * port, additionally enable forwarding of unknown unicast and
+         * multicast addresses.
          */
         REG_WRITE(addr, 0x04,
-                        (p == ds->cpu_port) ? 0x373f : 0x0433);
+                        (p == ds->cpu_port) ?
+                         (ds->tag_protocol == htons(ETH_P_DSA)) ?
+                          0x053f : 0x373f :
+                         0x0433);
 
         /*
          * Port Control 1: disable trunking.  Also, if this is the
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 3cb331e98b89..8f8868dd4302 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -239,6 +239,11 @@ dsa_slave_create(struct dsa_switch *ds, struct device *parent,
         memcpy(slave_dev->dev_addr, master->dev_addr, ETH_ALEN);
         slave_dev->tx_queue_len = 0;
         switch (ds->tag_protocol) {
+#ifdef CONFIG_NET_DSA_TAG_DSA
+        case htons(ETH_P_DSA):
+                slave_dev->hard_start_xmit = dsa_xmit;
+                break;
+#endif
 #ifdef CONFIG_NET_DSA_TAG_EDSA
         case htons(ETH_P_EDSA):
                 slave_dev->hard_start_xmit = edsa_xmit;
diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c
new file mode 100644
index 000000000000..bdc0510b53b7
--- /dev/null
+++ b/net/dsa/tag_dsa.c
@@ -0,0 +1,194 @@
+/*
+ * net/dsa/tag_dsa.c - (Non-ethertype) DSA tagging
+ * Copyright (c) 2008 Marvell Semiconductor
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/netdevice.h>
+#include "dsa_priv.h"
+
+#define DSA_HLEN        4
+
+int dsa_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+        struct dsa_slave_priv *p = netdev_priv(dev);
+        u8 *dsa_header;
+
+        dev->stats.tx_packets++;
+        dev->stats.tx_bytes += skb->len;
+
+        /*
+         * Convert the outermost 802.1q tag to a DSA tag for tagged
+         * packets, or insert a DSA tag between the addresses and
+         * the ethertype field for untagged packets.
+         */
+        if (skb->protocol == htons(ETH_P_8021Q)) {
+                if (skb_cow_head(skb, 0) < 0)
+                        goto out_free;
+
+                /*
+                 * Construct tagged FROM_CPU DSA tag from 802.1q tag.
+                 */
+                dsa_header = skb->data + 2 * ETH_ALEN;
+                dsa_header[0] = 0x60;
+                dsa_header[1] = p->port << 3;
+
+                /*
+                 * Move CFI field from byte 2 to byte 1.
+                 */
+                if (dsa_header[2] & 0x10) {
+                        dsa_header[1] |= 0x01;
+                        dsa_header[2] &= ~0x10;
+                }
+        } else {
+                if (skb_cow_head(skb, DSA_HLEN) < 0)
+                        goto out_free;
+                skb_push(skb, DSA_HLEN);
+
+                memmove(skb->data, skb->data + DSA_HLEN, 2 * ETH_ALEN);
+
+                /*
+                 * Construct untagged FROM_CPU DSA tag.
+                 */
+                dsa_header = skb->data + 2 * ETH_ALEN;
+                dsa_header[0] = 0x40;
+                dsa_header[1] = p->port << 3;
+                dsa_header[2] = 0x00;
+                dsa_header[3] = 0x00;
+        }
+
+        skb->protocol = htons(ETH_P_DSA);
+
+        skb->dev = p->parent->master_netdev;
+        dev_queue_xmit(skb);
+
+        return NETDEV_TX_OK;
+
+out_free:
+        kfree_skb(skb);
+        return NETDEV_TX_OK;
+}
+
+static int dsa_rcv(struct sk_buff *skb, struct net_device *dev,
+                   struct packet_type *pt, struct net_device *orig_dev)
+{
+        struct dsa_switch *ds = dev->dsa_ptr;
+        u8 *dsa_header;
+        int source_port;
+
+        if (unlikely(ds == NULL))
+                goto out_drop;
+
+        skb = skb_unshare(skb, GFP_ATOMIC);
+        if (skb == NULL)
+                goto out;
+
+        if (unlikely(!pskb_may_pull(skb, DSA_HLEN)))
+                goto out_drop;
+
+        /*
+         * The ethertype field is part of the DSA header.
+         */
+        dsa_header = skb->data - 2;
+
+        /*
+         * Check that frame type is either TO_CPU or FORWARD, and
+         * that the source device is zero.
+         */
+        if ((dsa_header[0] & 0xdf) != 0x00 && (dsa_header[0] & 0xdf) != 0xc0)
+                goto out_drop;
+
+        /*
+         * Check that the source port is a registered DSA port.
+         */
+        source_port = (dsa_header[1] >> 3) & 0x1f;
+        if (source_port >= DSA_MAX_PORTS || ds->ports[source_port] == NULL)
+                goto out_drop;
+
+        /*
+         * Convert the DSA header to an 802.1q header if the 'tagged'
+         * bit in the DSA header is set.  If the 'tagged' bit is clear,
+         * delete the DSA header entirely.
+         */
+        if (dsa_header[0] & 0x20) {
+                u8 new_header[4];
+
+                /*
+                 * Insert 802.1q ethertype and copy the VLAN-related
+                 * fields, but clear the bit that will hold CFI (since
+                 * DSA uses that bit location for another purpose).
+                 */
+                new_header[0] = (ETH_P_8021Q >> 8) & 0xff;
+                new_header[1] = ETH_P_8021Q & 0xff;
+                new_header[2] = dsa_header[2] & ~0x10;
+                new_header[3] = dsa_header[3];
+
+                /*
+                 * Move CFI bit from its place in the DSA header to
+                 * its 802.1q-designated place.
+                 */
+                if (dsa_header[1] & 0x01)
+                        new_header[2] |= 0x10;
+
+                /*
+                 * Update packet checksum if skb is CHECKSUM_COMPLETE.
+                 */
+                if (skb->ip_summed == CHECKSUM_COMPLETE) {
+                        __wsum c = skb->csum;
+                        c = csum_add(c, csum_partial(new_header + 2, 2, 0));
+                        c = csum_sub(c, csum_partial(dsa_header + 2, 2, 0));
+                        skb->csum = c;
+                }
+
+                memcpy(dsa_header, new_header, DSA_HLEN);
+        } else {
+                /*
+                 * Remove DSA tag and update checksum.
+                 */
+                skb_pull_rcsum(skb, DSA_HLEN);
+                memmove(skb->data - ETH_HLEN,
+                        skb->data - ETH_HLEN - DSA_HLEN,
+                        2 * ETH_ALEN);
+        }
+
+        skb->dev = ds->ports[source_port];
+        skb_push(skb, ETH_HLEN);
+        skb->protocol = eth_type_trans(skb, skb->dev);
+
+        skb->dev->last_rx = jiffies;
+        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;
+}
+
+static struct packet_type dsa_packet_type = {
+        .type   = __constant_htons(ETH_P_DSA),
+        .func   = dsa_rcv,
+};
+
+static int __init dsa_init_module(void)
+{
+        dev_add_pack(&dsa_packet_type);
+        return 0;
+}
+module_init(dsa_init_module);
+
+static void __exit dsa_cleanup_module(void)
+{
+        dev_remove_pack(&dsa_packet_type);
+}
+module_exit(dsa_cleanup_module);
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index 647a9edee375..dae47e7a44d8 100644
--- a/net/ethernet/eth.c
+++ b/net/ethernet/eth.c
@@ -57,6 +57,7 @@
 #include <net/sock.h>
 #include <net/ipv6.h>
 #include <net/ip.h>
+#include <net/dsa.h>
 #include <asm/uaccess.h>
 #include <asm/system.h>
 
@@ -184,6 +185,15 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev)
                         skb->pkt_type = PACKET_OTHERHOST;
         }
 
+        /*
+         * Some variants of DSA tagging don't have an ethertype field
+         * at all, so we check here whether one of those tagging
+         * variants has been configured on the receiving interface,
+         * and if so, set skb->protocol without looking at the packet.
+         */
+        if (netdev_uses_dsa_tags(dev))
+                return htons(ETH_P_DSA);
+
         if (ntohs(eth->h_proto) >= 1536)
                 return eth->h_proto;