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authorLinus Torvalds <torvalds@linux-foundation.org>2014-10-08 21:40:54 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2014-10-08 21:40:54 -0400
commit35a9ad8af0bb0fa3525e6d0d20e32551d226f38e (patch)
tree15b4b33206818886d9cff371fd2163e073b70568 /net/dsa/tag_brcm.c
parentd5935b07da53f74726e2a65dd4281d0f2c70e5d4 (diff)
parent64b1f00a0830e1c53874067273a096b228d83d36 (diff)
downloadlinux-35a9ad8af0bb0fa3525e6d0d20e32551d226f38e.tar.bz2
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: "Most notable changes in here: 1) By far the biggest accomplishment, thanks to a large range of contributors, is the addition of multi-send for transmit. This is the result of discussions back in Chicago, and the hard work of several individuals. Now, when the ->ndo_start_xmit() method of a driver sees skb->xmit_more as true, it can choose to defer the doorbell telling the driver to start processing the new TX queue entires. skb->xmit_more means that the generic networking is guaranteed to call the driver immediately with another SKB to send. There is logic added to the qdisc layer to dequeue multiple packets at a time, and the handling mis-predicted offloads in software is now done with no locks held. Finally, pktgen is extended to have a "burst" parameter that can be used to test a multi-send implementation. Several drivers have xmit_more support: i40e, igb, ixgbe, mlx4, virtio_net Adding support is almost trivial, so export more drivers to support this optimization soon. I want to thank, in no particular or implied order, Jesper Dangaard Brouer, Eric Dumazet, Alexander Duyck, Tom Herbert, Jamal Hadi Salim, John Fastabend, Florian Westphal, Daniel Borkmann, David Tat, Hannes Frederic Sowa, and Rusty Russell. 2) PTP and timestamping support in bnx2x, from Michal Kalderon. 3) Allow adjusting the rx_copybreak threshold for a driver via ethtool, and add rx_copybreak support to enic driver. From Govindarajulu Varadarajan. 4) Significant enhancements to the generic PHY layer and the bcm7xxx driver in particular (EEE support, auto power down, etc.) from Florian Fainelli. 5) Allow raw buffers to be used for flow dissection, allowing drivers to determine the optimal "linear pull" size for devices that DMA into pools of pages. The objective is to get exactly the necessary amount of headers into the linear SKB area pre-pulled, but no more. The new interface drivers use is eth_get_headlen(). From WANG Cong, with driver conversions (several had their own by-hand duplicated implementations) by Alexander Duyck and Eric Dumazet. 6) Support checksumming more smoothly and efficiently for encapsulations, and add "foo over UDP" facility. From Tom Herbert. 7) Add Broadcom SF2 switch driver to DSA layer, from Florian Fainelli. 8) eBPF now can load programs via a system call and has an extensive testsuite. Alexei Starovoitov and Daniel Borkmann. 9) Major overhaul of the packet scheduler to use RCU in several major areas such as the classifiers and rate estimators. From John Fastabend. 10) Add driver for Intel FM10000 Ethernet Switch, from Alexander Duyck. 11) Rearrange TCP_SKB_CB() to reduce cache line misses, from Eric Dumazet. 12) Add Datacenter TCP congestion control algorithm support, From Florian Westphal. 13) Reorganize sk_buff so that __copy_skb_header() is significantly faster. From Eric Dumazet" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1558 commits) netlabel: directly return netlbl_unlabel_genl_init() net: add netdev_txq_bql_{enqueue, complete}_prefetchw() helpers net: description of dma_cookie cause make xmldocs warning cxgb4: clean up a type issue cxgb4: potential shift wrapping bug i40e: skb->xmit_more support net: fs_enet: Add NAPI TX net: fs_enet: Remove non NAPI RX r8169:add support for RTL8168EP net_sched: copy exts->type in tcf_exts_change() wimax: convert printk to pr_foo() af_unix: remove 0 assignment on static ipv6: Do not warn for informational ICMP messages, regardless of type. Update Intel Ethernet Driver maintainers list bridge: Save frag_max_size between PRE_ROUTING and POST_ROUTING tipc: fix bug in multicast congestion handling net: better IFF_XMIT_DST_RELEASE support net/mlx4_en: remove NETDEV_TX_BUSY 3c59x: fix bad split of cpu_to_le32(pci_map_single()) net: bcmgenet: fix Tx ring priority programming ...
Diffstat (limited to 'net/dsa/tag_brcm.c')
-rw-r--r--net/dsa/tag_brcm.c171
1 files changed, 171 insertions, 0 deletions
diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
new file mode 100644
index 000000000000..83d3572cdb20
--- /dev/null
+++ b/net/dsa/tag_brcm.c
@@ -0,0 +1,171 @@
+/*
+ * Broadcom tag support
+ *
+ * Copyright (C) 2014 Broadcom Corporation
+ *
+ * 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/slab.h>
+#include "dsa_priv.h"
+
+/* This tag length is 4 bytes, older ones were 6 bytes, we do not
+ * handle them
+ */
+#define BRCM_TAG_LEN 4
+
+/* Tag is constructed and desconstructed using byte by byte access
+ * because the tag is placed after the MAC Source Address, which does
+ * not make it 4-bytes aligned, so this might cause unaligned accesses
+ * on most systems where this is used.
+ */
+
+/* Ingress and egress opcodes */
+#define BRCM_OPCODE_SHIFT 5
+#define BRCM_OPCODE_MASK 0x7
+
+/* Ingress fields */
+/* 1st byte in the tag */
+#define BRCM_IG_TC_SHIFT 2
+#define BRCM_IG_TC_MASK 0x7
+/* 2nd byte in the tag */
+#define BRCM_IG_TE_MASK 0x3
+#define BRCM_IG_TS_SHIFT 7
+/* 3rd byte in the tag */
+#define BRCM_IG_DSTMAP2_MASK 1
+#define BRCM_IG_DSTMAP1_MASK 0xff
+
+/* Egress fields */
+
+/* 2nd byte in the tag */
+#define BRCM_EG_CID_MASK 0xff
+
+/* 3rd byte in the tag */
+#define BRCM_EG_RC_MASK 0xff
+#define BRCM_EG_RC_RSVD (3 << 6)
+#define BRCM_EG_RC_EXCEPTION (1 << 5)
+#define BRCM_EG_RC_PROT_SNOOP (1 << 4)
+#define BRCM_EG_RC_PROT_TERM (1 << 3)
+#define BRCM_EG_RC_SWITCH (1 << 2)
+#define BRCM_EG_RC_MAC_LEARN (1 << 1)
+#define BRCM_EG_RC_MIRROR (1 << 0)
+#define BRCM_EG_TC_SHIFT 5
+#define BRCM_EG_TC_MASK 0x7
+#define BRCM_EG_PID_MASK 0x1f
+
+static netdev_tx_t brcm_tag_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct dsa_slave_priv *p = netdev_priv(dev);
+ u8 *brcm_tag;
+
+ dev->stats.tx_packets++;
+ dev->stats.tx_bytes += skb->len;
+
+ if (skb_cow_head(skb, BRCM_TAG_LEN) < 0)
+ goto out_free;
+
+ skb_push(skb, BRCM_TAG_LEN);
+
+ memmove(skb->data, skb->data + BRCM_TAG_LEN, 2 * ETH_ALEN);
+
+ /* Build the tag after the MAC Source Address */
+ brcm_tag = skb->data + 2 * ETH_ALEN;
+
+ /* Set the ingress opcode, traffic class, tag enforcment is
+ * deprecated
+ */
+ brcm_tag[0] = (1 << BRCM_OPCODE_SHIFT) |
+ ((skb->priority << BRCM_IG_TC_SHIFT) & BRCM_IG_TC_MASK);
+ brcm_tag[1] = 0;
+ brcm_tag[2] = 0;
+ if (p->port == 8)
+ brcm_tag[2] = BRCM_IG_DSTMAP2_MASK;
+ brcm_tag[3] = (1 << p->port) & BRCM_IG_DSTMAP1_MASK;
+
+ /* Queue the SKB for transmission on the parent interface, but
+ * do not modify its EtherType
+ */
+ skb->dev = p->parent->dst->master_netdev;
+ dev_queue_xmit(skb);
+
+ return NETDEV_TX_OK;
+
+out_free:
+ kfree_skb(skb);
+ return NETDEV_TX_OK;
+}
+
+static int brcm_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 source_port;
+ u8 *brcm_tag;
+
+ if (unlikely(dst == NULL))
+ goto out_drop;
+
+ ds = dst->ds[0];
+
+ skb = skb_unshare(skb, GFP_ATOMIC);
+ if (skb == NULL)
+ goto out;
+
+ if (unlikely(!pskb_may_pull(skb, BRCM_TAG_LEN)))
+ goto out_drop;
+
+ /* skb->data points to the EtherType, the tag is right before it */
+ brcm_tag = skb->data - 2;
+
+ /* The opcode should never be different than 0b000 */
+ if (unlikely((brcm_tag[0] >> BRCM_OPCODE_SHIFT) & BRCM_OPCODE_MASK))
+ goto out_drop;
+
+ /* We should never see a reserved reason code without knowing how to
+ * handle it
+ */
+ WARN_ON(brcm_tag[2] & BRCM_EG_RC_RSVD);
+
+ /* Locate which port this is coming from */
+ source_port = brcm_tag[3] & BRCM_EG_PID_MASK;
+
+ /* Validate port against switch setup, either the port is totally */
+ if (source_port >= DSA_MAX_PORTS || ds->ports[source_port] == NULL)
+ goto out_drop;
+
+ /* Remove Broadcom tag and update checksum */
+ skb_pull_rcsum(skb, BRCM_TAG_LEN);
+
+ /* Move the Ethernet DA and SA */
+ memmove(skb->data - ETH_HLEN,
+ skb->data - ETH_HLEN - BRCM_TAG_LEN,
+ 2 * ETH_ALEN);
+
+ skb_push(skb, ETH_HLEN);
+ skb->pkt_type = PACKET_HOST;
+ skb->dev = ds->ports[source_port];
+ 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 brcm_netdev_ops = {
+ .xmit = brcm_tag_xmit,
+ .rcv = brcm_tag_rcv,
+};