/*
 * Copyright (c) 2007 Cisco Systems, Inc. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     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.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include "mlx4_ib.h"
#include <rdma/ib_addr.h>
#include <linux/inet.h>
#include <linux/string.h>
#include <rdma/ib_cache.h>

int mlx4_ib_resolve_grh(struct mlx4_ib_dev *dev, const struct ib_ah_attr *ah_attr,
			u8 *mac, int *is_mcast, u8 port)
{
	struct mlx4_ib_iboe *iboe = &dev->iboe;
	struct in6_addr in6;

	*is_mcast = 0;
	spin_lock(&iboe->lock);
	if (!iboe->netdevs[port - 1]) {
		spin_unlock(&iboe->lock);
		return -EINVAL;
	}
	spin_unlock(&iboe->lock);

	memcpy(&in6, ah_attr->grh.dgid.raw, sizeof in6);
	if (rdma_link_local_addr(&in6))
		rdma_get_ll_mac(&in6, mac);
	else if (rdma_is_multicast_addr(&in6)) {
		rdma_get_mcast_mac(&in6, mac);
		*is_mcast = 1;
	} else
		return -EINVAL;

	return 0;
}

static struct ib_ah *create_ib_ah(struct ib_pd *pd, struct ib_ah_attr *ah_attr,
				  struct mlx4_ib_ah *ah)
{
	struct mlx4_dev *dev = to_mdev(pd->device)->dev;

	ah->av.ib.port_pd = cpu_to_be32(to_mpd(pd)->pdn | (ah_attr->port_num << 24));
	ah->av.ib.g_slid  = ah_attr->src_path_bits;
	if (ah_attr->ah_flags & IB_AH_GRH) {
		ah->av.ib.g_slid   |= 0x80;
		ah->av.ib.gid_index = ah_attr->grh.sgid_index;
		ah->av.ib.hop_limit = ah_attr->grh.hop_limit;
		ah->av.ib.sl_tclass_flowlabel |=
			cpu_to_be32((ah_attr->grh.traffic_class << 20) |
				    ah_attr->grh.flow_label);
		memcpy(ah->av.ib.dgid, ah_attr->grh.dgid.raw, 16);
	}

	ah->av.ib.dlid    = cpu_to_be16(ah_attr->dlid);
	if (ah_attr->static_rate) {
		ah->av.ib.stat_rate = ah_attr->static_rate + MLX4_STAT_RATE_OFFSET;
		while (ah->av.ib.stat_rate > IB_RATE_2_5_GBPS + MLX4_STAT_RATE_OFFSET &&
		       !(1 << ah->av.ib.stat_rate & dev->caps.stat_rate_support))
			--ah->av.ib.stat_rate;
	}
	ah->av.ib.sl_tclass_flowlabel = cpu_to_be32(ah_attr->sl << 28);

	return &ah->ibah;
}

static struct ib_ah *create_iboe_ah(struct ib_pd *pd, struct ib_ah_attr *ah_attr,
				   struct mlx4_ib_ah *ah)
{
	struct mlx4_ib_dev *ibdev = to_mdev(pd->device);
	struct mlx4_dev *dev = ibdev->dev;
	u8 mac[6];
	int err;
	int is_mcast;
	u16 vlan_tag;
	union ib_gid sgid;

	err = mlx4_ib_resolve_grh(ibdev, ah_attr, mac, &is_mcast, ah_attr->port_num);
	if (err)
		return ERR_PTR(err);

	memcpy(ah->av.eth.mac, mac, 6);
	err = ib_get_cached_gid(pd->device, ah_attr->port_num, ah_attr->grh.sgid_index, &sgid);
	if (err)
		return ERR_PTR(err);
	vlan_tag = rdma_get_vlan_id(&sgid);
	if (vlan_tag < 0x1000)
		vlan_tag |= (ah_attr->sl & 7) << 13;
	ah->av.eth.port_pd = cpu_to_be32(to_mpd(pd)->pdn | (ah_attr->port_num << 24));
	ah->av.eth.gid_index = ah_attr->grh.sgid_index;
	ah->av.eth.vlan = cpu_to_be16(vlan_tag);
	if (ah_attr->static_rate) {
		ah->av.eth.stat_rate = ah_attr->static_rate + MLX4_STAT_RATE_OFFSET;
		while (ah->av.eth.stat_rate > IB_RATE_2_5_GBPS + MLX4_STAT_RATE_OFFSET &&
		       !(1 << ah->av.eth.stat_rate & dev->caps.stat_rate_support))
			--ah->av.eth.stat_rate;
	}

	/*
	 * HW requires multicast LID so we just choose one.
	 */
	if (is_mcast)
		ah->av.ib.dlid = cpu_to_be16(0xc000);

	memcpy(ah->av.eth.dgid, ah_attr->grh.dgid.raw, 16);
	ah->av.eth.sl_tclass_flowlabel = cpu_to_be32(ah_attr->sl << 28);

	return &ah->ibah;
}

struct ib_ah *mlx4_ib_create_ah(struct ib_pd *pd, struct ib_ah_attr *ah_attr)
{
	struct mlx4_ib_ah *ah;
	struct ib_ah *ret;

	ah = kzalloc(sizeof *ah, GFP_ATOMIC);
	if (!ah)
		return ERR_PTR(-ENOMEM);

	if (rdma_port_get_link_layer(pd->device, ah_attr->port_num) == IB_LINK_LAYER_ETHERNET) {
		if (!(ah_attr->ah_flags & IB_AH_GRH)) {
			ret = ERR_PTR(-EINVAL);
			goto out;
		} else {
			/* TBD: need to handle the case when we get called
			in an atomic context and there we might sleep. We
			don't expect this currently since we're working with
			link local addresses which we can translate without
			going to sleep */
			ret = create_iboe_ah(pd, ah_attr, ah);
			if (IS_ERR(ret))
				goto out;
			else
				return ret;
		}
	} else
		return create_ib_ah(pd, ah_attr, ah); /* never fails */

out:
	kfree(ah);
	return ret;
}

int mlx4_ib_query_ah(struct ib_ah *ibah, struct ib_ah_attr *ah_attr)
{
	struct mlx4_ib_ah *ah = to_mah(ibah);
	enum rdma_link_layer ll;

	memset(ah_attr, 0, sizeof *ah_attr);
	ah_attr->sl = be32_to_cpu(ah->av.ib.sl_tclass_flowlabel) >> 28;
	ah_attr->port_num = be32_to_cpu(ah->av.ib.port_pd) >> 24;
	ll = rdma_port_get_link_layer(ibah->device, ah_attr->port_num);
	ah_attr->dlid = ll == IB_LINK_LAYER_INFINIBAND ? be16_to_cpu(ah->av.ib.dlid) : 0;
	if (ah->av.ib.stat_rate)
		ah_attr->static_rate = ah->av.ib.stat_rate - MLX4_STAT_RATE_OFFSET;
	ah_attr->src_path_bits = ah->av.ib.g_slid & 0x7F;

	if (mlx4_ib_ah_grh_present(ah)) {
		ah_attr->ah_flags = IB_AH_GRH;

		ah_attr->grh.traffic_class =
			be32_to_cpu(ah->av.ib.sl_tclass_flowlabel) >> 20;
		ah_attr->grh.flow_label =
			be32_to_cpu(ah->av.ib.sl_tclass_flowlabel) & 0xfffff;
		ah_attr->grh.hop_limit  = ah->av.ib.hop_limit;
		ah_attr->grh.sgid_index = ah->av.ib.gid_index;
		memcpy(ah_attr->grh.dgid.raw, ah->av.ib.dgid, 16);
	}

	return 0;
}

int mlx4_ib_destroy_ah(struct ib_ah *ah)
{
	kfree(to_mah(ah));
	return 0;
}