drivers/infiniband/ulp/opa_vnic/opa_vnic_encap.c - linux/torvalds/linux - Git at Google

 /*
  * Copyright(c) 2017 Intel Corporation.
  *
  * This file is provided under a dual BSD/GPLv2 license.  When using or
  * redistributing this file, you may do so under either license.
  *
  * GPL LICENSE SUMMARY
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License 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.
  *
  * BSD LICENSE
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  *  - Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  *  - Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
  *  - Neither the name of Intel Corporation nor the names of its
  *    contributors may be used to endorse or promote products derived
  *    from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  */

 /*
  * This file contains OPA VNIC encapsulation/decapsulation function.
  */

 #include <linux/if_ether.h>
 #include <linux/if_vlan.h>

 #include "opa_vnic_internal.h"

 /* OPA 16B Header fields */
 #define OPA_16B_LID_MASK        0xFFFFFull
 #define OPA_16B_SLID_HIGH_SHFT  8
 #define OPA_16B_SLID_MASK       0xF00ull
 #define OPA_16B_DLID_MASK       0xF000ull
 #define OPA_16B_DLID_HIGH_SHFT  12
 #define OPA_16B_LEN_SHFT        20
 #define OPA_16B_SC_SHFT         20
 #define OPA_16B_RC_SHFT         25
 #define OPA_16B_PKEY_SHFT       16

 #define OPA_VNIC_L4_HDR_SHFT    16

 /* L2+L4 hdr len is 20 bytes (5 quad words) */
 #define OPA_VNIC_HDR_QW_LEN   5

 static inline void opa_vnic_make_header(u8 *hdr, u32 slid, u32 dlid, u16 len,
 					u16 pkey, u16 entropy, u8 sc, u8 rc,
 					u8 l4_type, u16 l4_hdr)
 {
 	/* h[1]: LT=1, 16B L2=10 */
 	u32 h[OPA_VNIC_HDR_QW_LEN] = {0, 0xc0000000, 0, 0, 0};

 	h[2] = l4_type;
 	h[3] = entropy;
 	h[4] = l4_hdr << OPA_VNIC_L4_HDR_SHFT;

 	/* Extract and set 4 upper bits and 20 lower bits of the lids */
 	h[0] |= (slid & OPA_16B_LID_MASK);
 	h[2] |= ((slid >> (20 - OPA_16B_SLID_HIGH_SHFT)) & OPA_16B_SLID_MASK);

 	h[1] |= (dlid & OPA_16B_LID_MASK);
 	h[2] |= ((dlid >> (20 - OPA_16B_DLID_HIGH_SHFT)) & OPA_16B_DLID_MASK);

 	h[0] |= (len << OPA_16B_LEN_SHFT);
 	h[1] |= (rc << OPA_16B_RC_SHFT);
 	h[1] |= (sc << OPA_16B_SC_SHFT);
 	h[2] |= ((u32)pkey << OPA_16B_PKEY_SHFT);

 	memcpy(hdr, h, OPA_VNIC_HDR_LEN);
 }

 /*
  * Using a simple hash table for mac table implementation with the last octet
  * of mac address as a key.
  */
 static void opa_vnic_free_mac_tbl(struct hlist_head *mactbl)
 {
 	struct opa_vnic_mac_tbl_node *node;
 	struct hlist_node *tmp;
 	int bkt;

 	if (!mactbl)
 		return;

 	vnic_hash_for_each_safe(mactbl, bkt, tmp, node, hlist) {
 		hash_del(&node->hlist);
 		kfree(node);
 	}
 	kfree(mactbl);
 }

 static struct hlist_head *opa_vnic_alloc_mac_tbl(void)
 {
 	u32 size = sizeof(struct hlist_head) * OPA_VNIC_MAC_TBL_SIZE;
 	struct hlist_head *mactbl;

 	mactbl = kzalloc(size, GFP_KERNEL);
 	if (!mactbl)
 		return ERR_PTR(-ENOMEM);

 	vnic_hash_init(mactbl);
 	return mactbl;
 }

 /* opa_vnic_release_mac_tbl - empty and free the mac table */
 void opa_vnic_release_mac_tbl(struct opa_vnic_adapter *adapter)
 {
 	struct hlist_head *mactbl;

 	mutex_lock(&adapter->mactbl_lock);
 	mactbl = rcu_access_pointer(adapter->mactbl);
 	rcu_assign_pointer(adapter->mactbl, NULL);
 	synchronize_rcu();
 	opa_vnic_free_mac_tbl(mactbl);
 	adapter->info.vport.mac_tbl_digest = 0;
 	mutex_unlock(&adapter->mactbl_lock);
 }

 /*
  * opa_vnic_query_mac_tbl - query the mac table for a section
  *
  * This function implements query of specific function of the mac table.
  * The function also expects the requested range to be valid.
  */
 void opa_vnic_query_mac_tbl(struct opa_vnic_adapter *adapter,
 			    struct opa_veswport_mactable *tbl)
 {
 	struct opa_vnic_mac_tbl_node *node;
 	struct hlist_head *mactbl;
 	int bkt;
 	u16 loffset, lnum_entries;

 	rcu_read_lock();
 	mactbl = rcu_dereference(adapter->mactbl);
 	if (!mactbl)
 		goto get_mac_done;

 	loffset = be16_to_cpu(tbl->offset);
 	lnum_entries = be16_to_cpu(tbl->num_entries);

 	vnic_hash_for_each(mactbl, bkt, node, hlist) {
 		struct __opa_vnic_mactable_entry *nentry = &node->entry;
 		struct opa_veswport_mactable_entry *entry;

 		if ((node->index < loffset) ||
 		    (node->index >= (loffset + lnum_entries)))
 			continue;

 		/* populate entry in the tbl corresponding to the index */
 		entry = &tbl->tbl_entries[node->index - loffset];
 		memcpy(entry->mac_addr, nentry->mac_addr,
 		       ARRAY_SIZE(entry->mac_addr));
 		memcpy(entry->mac_addr_mask, nentry->mac_addr_mask,
 		       ARRAY_SIZE(entry->mac_addr_mask));
 		entry->dlid_sd = cpu_to_be32(nentry->dlid_sd);
 	}
 	tbl->mac_tbl_digest = cpu_to_be32(adapter->info.vport.mac_tbl_digest);
 get_mac_done:
 	rcu_read_unlock();
 }

 /*
  * opa_vnic_update_mac_tbl - update mac table section
  *
  * This function updates the specified section of the mac table.
  * The procedure includes following steps.
  *  - Allocate a new mac (hash) table.
  *  - Add the specified entries to the new table.
  *    (except the ones that are requested to be deleted).
  *  - Add all the other entries from the old mac table.
  *  - If there is a failure, free the new table and return.
  *  - Switch to the new table.
  *  - Free the old table and return.
  *
  * The function also expects the requested range to be valid.
  */
 int opa_vnic_update_mac_tbl(struct opa_vnic_adapter *adapter,
 			    struct opa_veswport_mactable *tbl)
 {
 	struct opa_vnic_mac_tbl_node *node, *new_node;
 	struct hlist_head *new_mactbl, *old_mactbl;
 	int i, bkt, rc = 0;
 	u8 key;
 	u16 loffset, lnum_entries;

 	mutex_lock(&adapter->mactbl_lock);
 	/* allocate new mac table */
 	new_mactbl = opa_vnic_alloc_mac_tbl();
 	if (IS_ERR(new_mactbl)) {
 		mutex_unlock(&adapter->mactbl_lock);
 		return PTR_ERR(new_mactbl);
 	}

 	loffset = be16_to_cpu(tbl->offset);
 	lnum_entries = be16_to_cpu(tbl->num_entries);

 	/* add updated entries to the new mac table */
 	for (i = 0; i < lnum_entries; i++) {
 		struct __opa_vnic_mactable_entry *nentry;
 		struct opa_veswport_mactable_entry *entry =
 							&tbl->tbl_entries[i];
 		u8 *mac_addr = entry->mac_addr;
 		u8 empty_mac[ETH_ALEN] = { 0 };

 		v_dbg("new mac entry %4d: %02x:%02x:%02x:%02x:%02x:%02x %x\n",
 		      loffset + i, mac_addr[0], mac_addr[1], mac_addr[2],
 		      mac_addr[3], mac_addr[4], mac_addr[5],
 		      entry->dlid_sd);

 		/* if the entry is being removed, do not add it */
 		if (!memcmp(mac_addr, empty_mac, ARRAY_SIZE(empty_mac)))
 			continue;

 		node = kzalloc(sizeof(*node), GFP_KERNEL);
 		if (!node) {
 			rc = -ENOMEM;
 			goto updt_done;
 		}

 		node->index = loffset + i;
 		nentry = &node->entry;
 		memcpy(nentry->mac_addr, entry->mac_addr,
 		       ARRAY_SIZE(nentry->mac_addr));
 		memcpy(nentry->mac_addr_mask, entry->mac_addr_mask,
 		       ARRAY_SIZE(nentry->mac_addr_mask));
 		nentry->dlid_sd = be32_to_cpu(entry->dlid_sd);
 		key = node->entry.mac_addr[OPA_VNIC_MAC_HASH_IDX];
 		vnic_hash_add(new_mactbl, &node->hlist, key);
 	}

 	/* add other entries from current mac table to new mac table */
 	old_mactbl = rcu_access_pointer(adapter->mactbl);
 	if (!old_mactbl)
 		goto switch_tbl;

 	vnic_hash_for_each(old_mactbl, bkt, node, hlist) {
 		if ((node->index >= loffset) &&
 		    (node->index < (loffset + lnum_entries)))
 			continue;

 		new_node = kzalloc(sizeof(*new_node), GFP_KERNEL);
 		if (!new_node) {
 			rc = -ENOMEM;
 			goto updt_done;
 		}

 		new_node->index = node->index;
 		memcpy(&new_node->entry, &node->entry, sizeof(node->entry));
 		key = new_node->entry.mac_addr[OPA_VNIC_MAC_HASH_IDX];
 		vnic_hash_add(new_mactbl, &new_node->hlist, key);
 	}

 switch_tbl:
 	/* switch to new table */
 	rcu_assign_pointer(adapter->mactbl, new_mactbl);
 	synchronize_rcu();

 	adapter->info.vport.mac_tbl_digest = be32_to_cpu(tbl->mac_tbl_digest);
 updt_done:
 	/* upon failure, free the new table; otherwise, free the old table */
 	if (rc)
 		opa_vnic_free_mac_tbl(new_mactbl);
 	else
 		opa_vnic_free_mac_tbl(old_mactbl);

 	mutex_unlock(&adapter->mactbl_lock);
 	return rc;
 }

 /* opa_vnic_chk_mac_tbl - check mac table for dlid */
 static uint32_t opa_vnic_chk_mac_tbl(struct opa_vnic_adapter *adapter,
 				     struct ethhdr *mac_hdr)
 {
 	struct opa_vnic_mac_tbl_node *node;
 	struct hlist_head *mactbl;
 	u32 dlid = 0;
 	u8 key;

 	rcu_read_lock();
 	mactbl = rcu_dereference(adapter->mactbl);
 	if (unlikely(!mactbl))
 		goto chk_done;

 	key = mac_hdr->h_dest[OPA_VNIC_MAC_HASH_IDX];
 	vnic_hash_for_each_possible(mactbl, node, hlist, key) {
 		struct __opa_vnic_mactable_entry *entry = &node->entry;

 		/* if related to source mac, skip */
 		if (unlikely(OPA_VNIC_DLID_SD_IS_SRC_MAC(entry->dlid_sd)))
 			continue;

 		if (!memcmp(node->entry.mac_addr, mac_hdr->h_dest,
 			    ARRAY_SIZE(node->entry.mac_addr))) {
 			/* mac address found */
 			dlid = OPA_VNIC_DLID_SD_GET_DLID(node->entry.dlid_sd);
 			break;
 		}
 	}

 chk_done:
 	rcu_read_unlock();
 	return dlid;
 }

 /* opa_vnic_get_dlid - find and return the DLID */
 static uint32_t opa_vnic_get_dlid(struct opa_vnic_adapter *adapter,
 				  struct sk_buff *skb, u8 def_port)
 {
 	struct __opa_veswport_info *info = &adapter->info;
 	struct ethhdr *mac_hdr = (struct ethhdr *)skb_mac_header(skb);
 	u32 dlid;

 	dlid = opa_vnic_chk_mac_tbl(adapter, mac_hdr);
 	if (dlid)
 		return dlid;

 	if (is_multicast_ether_addr(mac_hdr->h_dest)) {
 		dlid = info->vesw.u_mcast_dlid;
 	} else {
 		if (is_local_ether_addr(mac_hdr->h_dest)) {
 			dlid = ((uint32_t)mac_hdr->h_dest[5] << 16) |
 				((uint32_t)mac_hdr->h_dest[4] << 8)  |
 				mac_hdr->h_dest[3];
 			if (unlikely(!dlid))
 				v_warn("Null dlid in MAC address\n");
 		} else if (def_port != OPA_VNIC_INVALID_PORT) {
 			if (def_port < OPA_VESW_MAX_NUM_DEF_PORT)
 				dlid = info->vesw.u_ucast_dlid[def_port];
 		}
 	}

 	return dlid;
 }

 /* opa_vnic_get_sc - return the service class */
 static u8 opa_vnic_get_sc(struct __opa_veswport_info *info,
 			  struct sk_buff *skb)
 {
 	struct ethhdr *mac_hdr = (struct ethhdr *)skb_mac_header(skb);
 	u16 vlan_tci;
 	u8 sc;

 	if (!__vlan_get_tag(skb, &vlan_tci)) {
 		u8 pcp = OPA_VNIC_VLAN_PCP(vlan_tci);

 		if (is_multicast_ether_addr(mac_hdr->h_dest))
 			sc = info->vport.pcp_to_sc_mc[pcp];
 		else
 			sc = info->vport.pcp_to_sc_uc[pcp];
 	} else {
 		if (is_multicast_ether_addr(mac_hdr->h_dest))
 			sc = info->vport.non_vlan_sc_mc;
 		else
 			sc = info->vport.non_vlan_sc_uc;
 	}

 	return sc;
 }

 u8 opa_vnic_get_vl(struct opa_vnic_adapter *adapter, struct sk_buff *skb)
 {
 	struct ethhdr *mac_hdr = (struct ethhdr *)skb_mac_header(skb);
 	struct __opa_veswport_info *info = &adapter->info;
 	u8 vl;

 	if (skb_vlan_tag_present(skb)) {
 		u8 pcp = skb_vlan_tag_get(skb) >> VLAN_PRIO_SHIFT;

 		if (is_multicast_ether_addr(mac_hdr->h_dest))
 			vl = info->vport.pcp_to_vl_mc[pcp];
 		else
 			vl = info->vport.pcp_to_vl_uc[pcp];
 	} else {
 		if (is_multicast_ether_addr(mac_hdr->h_dest))
 			vl = info->vport.non_vlan_vl_mc;
 		else
 			vl = info->vport.non_vlan_vl_uc;
 	}

 	return vl;
 }

 /* opa_vnic_get_rc - return the routing control */
 static u8 opa_vnic_get_rc(struct __opa_veswport_info *info,
 			  struct sk_buff *skb)
 {
 	u8 proto, rout_ctrl;

 	switch (vlan_get_protocol(skb)) {
 	case htons(ETH_P_IPV6):
 		proto = ipv6_hdr(skb)->nexthdr;
 		if (proto == IPPROTO_TCP)
 			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
 							  IPV6_TCP);
 		else if (proto == IPPROTO_UDP)
 			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
 							  IPV6_UDP);
 		else
 			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc, IPV6);
 		break;
 	case htons(ETH_P_IP):
 		proto = ip_hdr(skb)->protocol;
 		if (proto == IPPROTO_TCP)
 			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
 							  IPV4_TCP);
 		else if (proto == IPPROTO_UDP)
 			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
 							  IPV4_UDP);
 		else
 			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc, IPV4);
 		break;
 	default:
 		rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc, DEFAULT);
 	}

 	return rout_ctrl;
 }

 /* opa_vnic_calc_entropy - calculate the packet entropy */
 u8 opa_vnic_calc_entropy(struct sk_buff *skb)
 {
 	u32 hash = skb_get_hash(skb);

 	/* store XOR of all bytes in lower 8 bits */
 	hash ^= hash >> 8;
 	hash ^= hash >> 16;

 	/* return lower 8 bits as entropy */
 	return (u8)(hash & 0xFF);
 }

 /* opa_vnic_get_def_port - get default port based on entropy */
 static inline u8 opa_vnic_get_def_port(struct opa_vnic_adapter *adapter,
 				       u8 entropy)
 {
 	u8 flow_id;

 	/* Add the upper and lower 4-bits of entropy to get the flow id */
 	flow_id = ((entropy & 0xf) + (entropy >> 4));
 	return adapter->flow_tbl[flow_id & (OPA_VNIC_FLOW_TBL_SIZE - 1)];
 }

 /* Calculate packet length including OPA header, crc and padding */
 static inline int opa_vnic_wire_length(struct sk_buff *skb)
 {
 	u32 pad_len;

 	/* padding for 8 bytes size alignment */
 	pad_len = -(skb->len + OPA_VNIC_ICRC_TAIL_LEN) & 0x7;
 	pad_len += OPA_VNIC_ICRC_TAIL_LEN;

 	return (skb->len + pad_len) >> 3;
 }

 /* opa_vnic_encap_skb - encapsulate skb packet with OPA header and meta data */
 void opa_vnic_encap_skb(struct opa_vnic_adapter *adapter, struct sk_buff *skb)
 {
 	struct __opa_veswport_info *info = &adapter->info;
 	struct opa_vnic_skb_mdata *mdata;
 	u8 def_port, sc, rc, entropy, *hdr;
 	u16 len, l4_hdr;
 	u32 dlid;

 	hdr = skb_push(skb, OPA_VNIC_HDR_LEN);

 	entropy = opa_vnic_calc_entropy(skb);
 	def_port = opa_vnic_get_def_port(adapter, entropy);
 	len = opa_vnic_wire_length(skb);
 	dlid = opa_vnic_get_dlid(adapter, skb, def_port);
 	sc = opa_vnic_get_sc(info, skb);
 	rc = opa_vnic_get_rc(info, skb);
 	l4_hdr = info->vesw.vesw_id;

 	mdata = skb_push(skb, sizeof(*mdata));
 	mdata->vl = opa_vnic_get_vl(adapter, skb);
 	mdata->entropy = entropy;
 	mdata->flags = 0;
 	if (unlikely(!dlid)) {
 		mdata->flags = OPA_VNIC_SKB_MDATA_ENCAP_ERR;
 		return;
 	}

 	opa_vnic_make_header(hdr, info->vport.encap_slid, dlid, len,
 			     info->vesw.pkey, entropy, sc, rc,
 			     OPA_VNIC_L4_ETHR, l4_hdr);
 }
	/*
	* Copyright(c) 2017 Intel Corporation.
	*
	* This file is provided under a dual BSD/GPLv2 license. When using or
	* redistributing this file, you may do so under either license.
	*
	* GPL LICENSE SUMMARY
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of version 2 of the GNU General Public License 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.
	*
	* BSD LICENSE
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	*
	* - Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* - Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in
	* the documentation and/or other materials provided with the
	* distribution.
	* - Neither the name of Intel Corporation nor the names of its
	* contributors may be used to endorse or promote products derived
	* from this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*
	*/

	/*
	* This file contains OPA VNIC encapsulation/decapsulation function.
	*/

	#include <linux/if_ether.h>
	#include <linux/if_vlan.h>

	#include "opa_vnic_internal.h"

	/* OPA 16B Header fields */
	#define OPA_16B_LID_MASK 0xFFFFFull
	#define OPA_16B_SLID_HIGH_SHFT 8
	#define OPA_16B_SLID_MASK 0xF00ull
	#define OPA_16B_DLID_MASK 0xF000ull
	#define OPA_16B_DLID_HIGH_SHFT 12
	#define OPA_16B_LEN_SHFT 20
	#define OPA_16B_SC_SHFT 20
	#define OPA_16B_RC_SHFT 25
	#define OPA_16B_PKEY_SHFT 16

	#define OPA_VNIC_L4_HDR_SHFT 16

	/* L2+L4 hdr len is 20 bytes (5 quad words) */
	#define OPA_VNIC_HDR_QW_LEN 5

	static inline void opa_vnic_make_header(u8 *hdr, u32 slid, u32 dlid, u16 len,
	u16 pkey, u16 entropy, u8 sc, u8 rc,
	u8 l4_type, u16 l4_hdr)
	{
	/* h[1]: LT=1, 16B L2=10 */
	u32 h[OPA_VNIC_HDR_QW_LEN] = {0, 0xc0000000, 0, 0, 0};

	h[2] = l4_type;
	h[3] = entropy;
	h[4] = l4_hdr << OPA_VNIC_L4_HDR_SHFT;

	/* Extract and set 4 upper bits and 20 lower bits of the lids */
	h[0] \|= (slid & OPA_16B_LID_MASK);
	h[2] \|= ((slid >> (20 - OPA_16B_SLID_HIGH_SHFT)) & OPA_16B_SLID_MASK);

	h[1] \|= (dlid & OPA_16B_LID_MASK);
	h[2] \|= ((dlid >> (20 - OPA_16B_DLID_HIGH_SHFT)) & OPA_16B_DLID_MASK);

	h[0] \|= (len << OPA_16B_LEN_SHFT);
	h[1] \|= (rc << OPA_16B_RC_SHFT);
	h[1] \|= (sc << OPA_16B_SC_SHFT);
	h[2] \|= ((u32)pkey << OPA_16B_PKEY_SHFT);

	memcpy(hdr, h, OPA_VNIC_HDR_LEN);
	}

	/*
	* Using a simple hash table for mac table implementation with the last octet
	* of mac address as a key.
	*/
	static void opa_vnic_free_mac_tbl(struct hlist_head *mactbl)
	{
	struct opa_vnic_mac_tbl_node *node;
	struct hlist_node *tmp;
	int bkt;

	if (!mactbl)
	return;

	vnic_hash_for_each_safe(mactbl, bkt, tmp, node, hlist) {
	hash_del(&node->hlist);
	kfree(node);
	}
	kfree(mactbl);
	}

	static struct hlist_head *opa_vnic_alloc_mac_tbl(void)
	{
	u32 size = sizeof(struct hlist_head) * OPA_VNIC_MAC_TBL_SIZE;
	struct hlist_head *mactbl;

	mactbl = kzalloc(size, GFP_KERNEL);
	if (!mactbl)
	return ERR_PTR(-ENOMEM);

	vnic_hash_init(mactbl);
	return mactbl;
	}

	/* opa_vnic_release_mac_tbl - empty and free the mac table */
	void opa_vnic_release_mac_tbl(struct opa_vnic_adapter *adapter)
	{
	struct hlist_head *mactbl;

	mutex_lock(&adapter->mactbl_lock);
	mactbl = rcu_access_pointer(adapter->mactbl);
	rcu_assign_pointer(adapter->mactbl, NULL);
	synchronize_rcu();
	opa_vnic_free_mac_tbl(mactbl);
	adapter->info.vport.mac_tbl_digest = 0;
	mutex_unlock(&adapter->mactbl_lock);
	}

	/*
	* opa_vnic_query_mac_tbl - query the mac table for a section
	*
	* This function implements query of specific function of the mac table.
	* The function also expects the requested range to be valid.
	*/
	void opa_vnic_query_mac_tbl(struct opa_vnic_adapter *adapter,
	struct opa_veswport_mactable *tbl)
	{
	struct opa_vnic_mac_tbl_node *node;
	struct hlist_head *mactbl;
	int bkt;
	u16 loffset, lnum_entries;

	rcu_read_lock();
	mactbl = rcu_dereference(adapter->mactbl);
	if (!mactbl)
	goto get_mac_done;

	loffset = be16_to_cpu(tbl->offset);
	lnum_entries = be16_to_cpu(tbl->num_entries);

	vnic_hash_for_each(mactbl, bkt, node, hlist) {
	struct __opa_vnic_mactable_entry *nentry = &node->entry;
	struct opa_veswport_mactable_entry *entry;

	if ((node->index < loffset) \|\|
	(node->index >= (loffset + lnum_entries)))
	continue;

	/* populate entry in the tbl corresponding to the index */
	entry = &tbl->tbl_entries[node->index - loffset];
	memcpy(entry->mac_addr, nentry->mac_addr,
	ARRAY_SIZE(entry->mac_addr));
	memcpy(entry->mac_addr_mask, nentry->mac_addr_mask,
	ARRAY_SIZE(entry->mac_addr_mask));
	entry->dlid_sd = cpu_to_be32(nentry->dlid_sd);
	}
	tbl->mac_tbl_digest = cpu_to_be32(adapter->info.vport.mac_tbl_digest);
	get_mac_done:
	rcu_read_unlock();
	}

	/*
	* opa_vnic_update_mac_tbl - update mac table section
	*
	* This function updates the specified section of the mac table.
	* The procedure includes following steps.
	* - Allocate a new mac (hash) table.
	* - Add the specified entries to the new table.
	* (except the ones that are requested to be deleted).
	* - Add all the other entries from the old mac table.
	* - If there is a failure, free the new table and return.
	* - Switch to the new table.
	* - Free the old table and return.
	*
	* The function also expects the requested range to be valid.
	*/
	int opa_vnic_update_mac_tbl(struct opa_vnic_adapter *adapter,
	struct opa_veswport_mactable *tbl)
	{
	struct opa_vnic_mac_tbl_node node, new_node;
	struct hlist_head new_mactbl, old_mactbl;
	int i, bkt, rc = 0;
	u8 key;
	u16 loffset, lnum_entries;

	mutex_lock(&adapter->mactbl_lock);
	/* allocate new mac table */
	new_mactbl = opa_vnic_alloc_mac_tbl();
	if (IS_ERR(new_mactbl)) {
	mutex_unlock(&adapter->mactbl_lock);
	return PTR_ERR(new_mactbl);
	}

	loffset = be16_to_cpu(tbl->offset);
	lnum_entries = be16_to_cpu(tbl->num_entries);

	/* add updated entries to the new mac table */
	for (i = 0; i < lnum_entries; i++) {
	struct __opa_vnic_mactable_entry *nentry;
	struct opa_veswport_mactable_entry *entry =
	&tbl->tbl_entries[i];
	u8 *mac_addr = entry->mac_addr;
	u8 empty_mac[ETH_ALEN] = { 0 };

	v_dbg("new mac entry %4d: %02x:%02x:%02x:%02x:%02x:%02x %x\n",
	loffset + i, mac_addr[0], mac_addr[1], mac_addr[2],
	mac_addr[3], mac_addr[4], mac_addr[5],
	entry->dlid_sd);

	/* if the entry is being removed, do not add it */
	if (!memcmp(mac_addr, empty_mac, ARRAY_SIZE(empty_mac)))
	continue;

	node = kzalloc(sizeof(*node), GFP_KERNEL);
	if (!node) {
	rc = -ENOMEM;
	goto updt_done;
	}

	node->index = loffset + i;
	nentry = &node->entry;
	memcpy(nentry->mac_addr, entry->mac_addr,
	ARRAY_SIZE(nentry->mac_addr));
	memcpy(nentry->mac_addr_mask, entry->mac_addr_mask,
	ARRAY_SIZE(nentry->mac_addr_mask));
	nentry->dlid_sd = be32_to_cpu(entry->dlid_sd);
	key = node->entry.mac_addr[OPA_VNIC_MAC_HASH_IDX];
	vnic_hash_add(new_mactbl, &node->hlist, key);
	}

	/* add other entries from current mac table to new mac table */
	old_mactbl = rcu_access_pointer(adapter->mactbl);
	if (!old_mactbl)
	goto switch_tbl;

	vnic_hash_for_each(old_mactbl, bkt, node, hlist) {
	if ((node->index >= loffset) &&
	(node->index < (loffset + lnum_entries)))
	continue;

	new_node = kzalloc(sizeof(*new_node), GFP_KERNEL);
	if (!new_node) {
	rc = -ENOMEM;
	goto updt_done;
	}

	new_node->index = node->index;
	memcpy(&new_node->entry, &node->entry, sizeof(node->entry));
	key = new_node->entry.mac_addr[OPA_VNIC_MAC_HASH_IDX];
	vnic_hash_add(new_mactbl, &new_node->hlist, key);
	}

	switch_tbl:
	/* switch to new table */
	rcu_assign_pointer(adapter->mactbl, new_mactbl);
	synchronize_rcu();

	adapter->info.vport.mac_tbl_digest = be32_to_cpu(tbl->mac_tbl_digest);
	updt_done:
	/* upon failure, free the new table; otherwise, free the old table */
	if (rc)
	opa_vnic_free_mac_tbl(new_mactbl);
	else
	opa_vnic_free_mac_tbl(old_mactbl);

	mutex_unlock(&adapter->mactbl_lock);
	return rc;
	}

	/* opa_vnic_chk_mac_tbl - check mac table for dlid */
	static uint32_t opa_vnic_chk_mac_tbl(struct opa_vnic_adapter *adapter,
	struct ethhdr *mac_hdr)
	{
	struct opa_vnic_mac_tbl_node *node;
	struct hlist_head *mactbl;
	u32 dlid = 0;
	u8 key;

	rcu_read_lock();
	mactbl = rcu_dereference(adapter->mactbl);
	if (unlikely(!mactbl))
	goto chk_done;

	key = mac_hdr->h_dest[OPA_VNIC_MAC_HASH_IDX];
	vnic_hash_for_each_possible(mactbl, node, hlist, key) {
	struct __opa_vnic_mactable_entry *entry = &node->entry;

	/* if related to source mac, skip */
	if (unlikely(OPA_VNIC_DLID_SD_IS_SRC_MAC(entry->dlid_sd)))
	continue;

	if (!memcmp(node->entry.mac_addr, mac_hdr->h_dest,
	ARRAY_SIZE(node->entry.mac_addr))) {
	/* mac address found */
	dlid = OPA_VNIC_DLID_SD_GET_DLID(node->entry.dlid_sd);
	break;
	}
	}

	chk_done:
	rcu_read_unlock();
	return dlid;
	}

	/* opa_vnic_get_dlid - find and return the DLID */
	static uint32_t opa_vnic_get_dlid(struct opa_vnic_adapter *adapter,
	struct sk_buff *skb, u8 def_port)
	{
	struct __opa_veswport_info *info = &adapter->info;
	struct ethhdr mac_hdr = (struct ethhdr )skb_mac_header(skb);
	u32 dlid;

	dlid = opa_vnic_chk_mac_tbl(adapter, mac_hdr);
	if (dlid)
	return dlid;

	if (is_multicast_ether_addr(mac_hdr->h_dest)) {
	dlid = info->vesw.u_mcast_dlid;
	} else {
	if (is_local_ether_addr(mac_hdr->h_dest)) {
	dlid = ((uint32_t)mac_hdr->h_dest[5] << 16) \|
	((uint32_t)mac_hdr->h_dest[4] << 8) \|
	mac_hdr->h_dest[3];
	if (unlikely(!dlid))
	v_warn("Null dlid in MAC address\n");
	} else if (def_port != OPA_VNIC_INVALID_PORT) {
	if (def_port < OPA_VESW_MAX_NUM_DEF_PORT)
	dlid = info->vesw.u_ucast_dlid[def_port];
	}
	}

	return dlid;
	}

	/* opa_vnic_get_sc - return the service class */
	static u8 opa_vnic_get_sc(struct __opa_veswport_info *info,
	struct sk_buff *skb)
	{
	struct ethhdr mac_hdr = (struct ethhdr )skb_mac_header(skb);
	u16 vlan_tci;
	u8 sc;

	if (!__vlan_get_tag(skb, &vlan_tci)) {
	u8 pcp = OPA_VNIC_VLAN_PCP(vlan_tci);

	if (is_multicast_ether_addr(mac_hdr->h_dest))
	sc = info->vport.pcp_to_sc_mc[pcp];
	else
	sc = info->vport.pcp_to_sc_uc[pcp];
	} else {
	if (is_multicast_ether_addr(mac_hdr->h_dest))
	sc = info->vport.non_vlan_sc_mc;
	else
	sc = info->vport.non_vlan_sc_uc;
	}

	return sc;
	}

	u8 opa_vnic_get_vl(struct opa_vnic_adapter adapter, struct sk_buff skb)
	{
	struct ethhdr mac_hdr = (struct ethhdr )skb_mac_header(skb);
	struct __opa_veswport_info *info = &adapter->info;
	u8 vl;

	if (skb_vlan_tag_present(skb)) {
	u8 pcp = skb_vlan_tag_get(skb) >> VLAN_PRIO_SHIFT;

	if (is_multicast_ether_addr(mac_hdr->h_dest))
	vl = info->vport.pcp_to_vl_mc[pcp];
	else
	vl = info->vport.pcp_to_vl_uc[pcp];
	} else {
	if (is_multicast_ether_addr(mac_hdr->h_dest))
	vl = info->vport.non_vlan_vl_mc;
	else
	vl = info->vport.non_vlan_vl_uc;
	}

	return vl;
	}

	/* opa_vnic_get_rc - return the routing control */
	static u8 opa_vnic_get_rc(struct __opa_veswport_info *info,
	struct sk_buff *skb)
	{
	u8 proto, rout_ctrl;

	switch (vlan_get_protocol(skb)) {
	case htons(ETH_P_IPV6):
	proto = ipv6_hdr(skb)->nexthdr;
	if (proto == IPPROTO_TCP)
	rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
	IPV6_TCP);
	else if (proto == IPPROTO_UDP)
	rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
	IPV6_UDP);
	else
	rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc, IPV6);
	break;
	case htons(ETH_P_IP):
	proto = ip_hdr(skb)->protocol;
	if (proto == IPPROTO_TCP)
	rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
	IPV4_TCP);
	else if (proto == IPPROTO_UDP)
	rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
	IPV4_UDP);
	else
	rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc, IPV4);
	break;
	default:
	rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc, DEFAULT);
	}

	return rout_ctrl;
	}

	/* opa_vnic_calc_entropy - calculate the packet entropy */
	u8 opa_vnic_calc_entropy(struct sk_buff *skb)
	{
	u32 hash = skb_get_hash(skb);

	/* store XOR of all bytes in lower 8 bits */
	hash ^= hash >> 8;
	hash ^= hash >> 16;

	/* return lower 8 bits as entropy */
	return (u8)(hash & 0xFF);
	}

	/* opa_vnic_get_def_port - get default port based on entropy */
	static inline u8 opa_vnic_get_def_port(struct opa_vnic_adapter *adapter,
	u8 entropy)
	{
	u8 flow_id;

	/* Add the upper and lower 4-bits of entropy to get the flow id */
	flow_id = ((entropy & 0xf) + (entropy >> 4));
	return adapter->flow_tbl[flow_id & (OPA_VNIC_FLOW_TBL_SIZE - 1)];
	}

	/* Calculate packet length including OPA header, crc and padding */
	static inline int opa_vnic_wire_length(struct sk_buff *skb)
	{
	u32 pad_len;

	/* padding for 8 bytes size alignment */
	pad_len = -(skb->len + OPA_VNIC_ICRC_TAIL_LEN) & 0x7;
	pad_len += OPA_VNIC_ICRC_TAIL_LEN;

	return (skb->len + pad_len) >> 3;
	}

	/* opa_vnic_encap_skb - encapsulate skb packet with OPA header and meta data */
	void opa_vnic_encap_skb(struct opa_vnic_adapter adapter, struct sk_buff skb)
	{
	struct __opa_veswport_info *info = &adapter->info;
	struct opa_vnic_skb_mdata *mdata;
	u8 def_port, sc, rc, entropy, *hdr;
	u16 len, l4_hdr;
	u32 dlid;

	hdr = skb_push(skb, OPA_VNIC_HDR_LEN);

	entropy = opa_vnic_calc_entropy(skb);
	def_port = opa_vnic_get_def_port(adapter, entropy);
	len = opa_vnic_wire_length(skb);
	dlid = opa_vnic_get_dlid(adapter, skb, def_port);
	sc = opa_vnic_get_sc(info, skb);
	rc = opa_vnic_get_rc(info, skb);
	l4_hdr = info->vesw.vesw_id;

	mdata = skb_push(skb, sizeof(*mdata));
	mdata->vl = opa_vnic_get_vl(adapter, skb);
	mdata->entropy = entropy;
	mdata->flags = 0;
	if (unlikely(!dlid)) {
	mdata->flags = OPA_VNIC_SKB_MDATA_ENCAP_ERR;
	return;
	}

	opa_vnic_make_header(hdr, info->vport.encap_slid, dlid, len,
	info->vesw.pkey, entropy, sc, rc,
	OPA_VNIC_L4_ETHR, l4_hdr);
	}