OpenCloudOS-Kernel/drivers/infiniband/core/verbs.c

/*
 * Copyright (c) 2004 Mellanox Technologies Ltd.  All rights reserved.
 * Copyright (c) 2004 Infinicon Corporation.  All rights reserved.
 * Copyright (c) 2004 Intel Corporation.  All rights reserved.
 * Copyright (c) 2004 Topspin Corporation.  All rights reserved.
 * Copyright (c) 2004 Voltaire Corporation.  All rights reserved.
 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
 * Copyright (c) 2005, 2006 Cisco Systems.  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 <linux/errno.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/string.h>
#include <linux/slab.h>

#include <rdma/ib_verbs.h>
#include <rdma/ib_cache.h>
#include <rdma/ib_addr.h>

int ib_rate_to_mult(enum ib_rate rate)
{
	switch (rate) {
	case IB_RATE_2_5_GBPS: return  1;
	case IB_RATE_5_GBPS:   return  2;
	case IB_RATE_10_GBPS:  return  4;
	case IB_RATE_20_GBPS:  return  8;
	case IB_RATE_30_GBPS:  return 12;
	case IB_RATE_40_GBPS:  return 16;
	case IB_RATE_60_GBPS:  return 24;
	case IB_RATE_80_GBPS:  return 32;
	case IB_RATE_120_GBPS: return 48;
	default:	       return -1;
	}
}
EXPORT_SYMBOL(ib_rate_to_mult);

enum ib_rate mult_to_ib_rate(int mult)
{
	switch (mult) {
	case 1:  return IB_RATE_2_5_GBPS;
	case 2:  return IB_RATE_5_GBPS;
	case 4:  return IB_RATE_10_GBPS;
	case 8:  return IB_RATE_20_GBPS;
	case 12: return IB_RATE_30_GBPS;
	case 16: return IB_RATE_40_GBPS;
	case 24: return IB_RATE_60_GBPS;
	case 32: return IB_RATE_80_GBPS;
	case 48: return IB_RATE_120_GBPS;
	default: return IB_RATE_PORT_CURRENT;
	}
}
EXPORT_SYMBOL(mult_to_ib_rate);

int ib_rate_to_mbps(enum ib_rate rate)
{
	switch (rate) {
	case IB_RATE_2_5_GBPS: return 2500;
	case IB_RATE_5_GBPS:   return 5000;
	case IB_RATE_10_GBPS:  return 10000;
	case IB_RATE_20_GBPS:  return 20000;
	case IB_RATE_30_GBPS:  return 30000;
	case IB_RATE_40_GBPS:  return 40000;
	case IB_RATE_60_GBPS:  return 60000;
	case IB_RATE_80_GBPS:  return 80000;
	case IB_RATE_120_GBPS: return 120000;
	case IB_RATE_14_GBPS:  return 14062;
	case IB_RATE_56_GBPS:  return 56250;
	case IB_RATE_112_GBPS: return 112500;
	case IB_RATE_168_GBPS: return 168750;
	case IB_RATE_25_GBPS:  return 25781;
	case IB_RATE_100_GBPS: return 103125;
	case IB_RATE_200_GBPS: return 206250;
	case IB_RATE_300_GBPS: return 309375;
	default:	       return -1;
	}
}
EXPORT_SYMBOL(ib_rate_to_mbps);

enum rdma_transport_type
rdma_node_get_transport(enum rdma_node_type node_type)
{
	switch (node_type) {
	case RDMA_NODE_IB_CA:
	case RDMA_NODE_IB_SWITCH:
	case RDMA_NODE_IB_ROUTER:
		return RDMA_TRANSPORT_IB;
	case RDMA_NODE_RNIC:
		return RDMA_TRANSPORT_IWARP;
	case RDMA_NODE_USNIC:
		return RDMA_TRANSPORT_USNIC;
	default:
		BUG();
		return 0;
	}
}
EXPORT_SYMBOL(rdma_node_get_transport);

enum rdma_link_layer rdma_port_get_link_layer(struct ib_device *device, u8 port_num)
{
	if (device->get_link_layer)
		return device->get_link_layer(device, port_num);

	switch (rdma_node_get_transport(device->node_type)) {
	case RDMA_TRANSPORT_IB:
		return IB_LINK_LAYER_INFINIBAND;
	case RDMA_TRANSPORT_IWARP:
	case RDMA_TRANSPORT_USNIC:
		return IB_LINK_LAYER_ETHERNET;
	default:
		return IB_LINK_LAYER_UNSPECIFIED;
	}
}
EXPORT_SYMBOL(rdma_port_get_link_layer);

/* Protection domains */

struct ib_pd *ib_alloc_pd(struct ib_device *device)
{
	struct ib_pd *pd;

	pd = device->alloc_pd(device, NULL, NULL);

	if (!IS_ERR(pd)) {
		pd->device  = device;
		pd->uobject = NULL;
		atomic_set(&pd->usecnt, 0);
	}

	return pd;
}
EXPORT_SYMBOL(ib_alloc_pd);

int ib_dealloc_pd(struct ib_pd *pd)
{
	if (atomic_read(&pd->usecnt))
		return -EBUSY;

	return pd->device->dealloc_pd(pd);
}
EXPORT_SYMBOL(ib_dealloc_pd);

/* Address handles */

struct ib_ah *ib_create_ah(struct ib_pd *pd, struct ib_ah_attr *ah_attr)
{
	struct ib_ah *ah;

	ah = pd->device->create_ah(pd, ah_attr);

	if (!IS_ERR(ah)) {
		ah->device  = pd->device;
		ah->pd      = pd;
		ah->uobject = NULL;
		atomic_inc(&pd->usecnt);
	}

	return ah;
}
EXPORT_SYMBOL(ib_create_ah);

int ib_init_ah_from_wc(struct ib_device *device, u8 port_num, struct ib_wc *wc,
		       struct ib_grh *grh, struct ib_ah_attr *ah_attr)
{
	u32 flow_class;
	u16 gid_index;
	int ret;
	int is_eth = (rdma_port_get_link_layer(device, port_num) ==
			IB_LINK_LAYER_ETHERNET);

	memset(ah_attr, 0, sizeof *ah_attr);
	if (is_eth) {
		if (!(wc->wc_flags & IB_WC_GRH))
			return -EPROTOTYPE;

		if (wc->wc_flags & IB_WC_WITH_SMAC &&
		    wc->wc_flags & IB_WC_WITH_VLAN) {
			memcpy(ah_attr->dmac, wc->smac, ETH_ALEN);
			ah_attr->vlan_id = wc->vlan_id;
		} else {
			ret = rdma_addr_find_dmac_by_grh(&grh->dgid, &grh->sgid,
					ah_attr->dmac, &ah_attr->vlan_id);
			if (ret)
				return ret;
		}
	} else {
		ah_attr->vlan_id = 0xffff;
	}

	ah_attr->dlid = wc->slid;
	ah_attr->sl = wc->sl;
	ah_attr->src_path_bits = wc->dlid_path_bits;
	ah_attr->port_num = port_num;

	if (wc->wc_flags & IB_WC_GRH) {
		ah_attr->ah_flags = IB_AH_GRH;
		ah_attr->grh.dgid = grh->sgid;

		ret = ib_find_cached_gid(device, &grh->dgid, &port_num,
					 &gid_index);
		if (ret)
			return ret;

		ah_attr->grh.sgid_index = (u8) gid_index;
		flow_class = be32_to_cpu(grh->version_tclass_flow);
		ah_attr->grh.flow_label = flow_class & 0xFFFFF;
		ah_attr->grh.hop_limit = 0xFF;
		ah_attr->grh.traffic_class = (flow_class >> 20) & 0xFF;
	}
	return 0;
}
EXPORT_SYMBOL(ib_init_ah_from_wc);

struct ib_ah *ib_create_ah_from_wc(struct ib_pd *pd, struct ib_wc *wc,
				   struct ib_grh *grh, u8 port_num)
{
	struct ib_ah_attr ah_attr;
	int ret;

	ret = ib_init_ah_from_wc(pd->device, port_num, wc, grh, &ah_attr);
	if (ret)
		return ERR_PTR(ret);

	return ib_create_ah(pd, &ah_attr);
}
EXPORT_SYMBOL(ib_create_ah_from_wc);

int ib_modify_ah(struct ib_ah *ah, struct ib_ah_attr *ah_attr)
{
	return ah->device->modify_ah ?
		ah->device->modify_ah(ah, ah_attr) :
		-ENOSYS;
}
EXPORT_SYMBOL(ib_modify_ah);

int ib_query_ah(struct ib_ah *ah, struct ib_ah_attr *ah_attr)
{
	return ah->device->query_ah ?
		ah->device->query_ah(ah, ah_attr) :
		-ENOSYS;
}
EXPORT_SYMBOL(ib_query_ah);

int ib_destroy_ah(struct ib_ah *ah)
{
	struct ib_pd *pd;
	int ret;

	pd = ah->pd;
	ret = ah->device->destroy_ah(ah);
	if (!ret)
		atomic_dec(&pd->usecnt);

	return ret;
}
EXPORT_SYMBOL(ib_destroy_ah);

/* Shared receive queues */

struct ib_srq *ib_create_srq(struct ib_pd *pd,
			     struct ib_srq_init_attr *srq_init_attr)
{
	struct ib_srq *srq;

	if (!pd->device->create_srq)
		return ERR_PTR(-ENOSYS);

	srq = pd->device->create_srq(pd, srq_init_attr, NULL);

	if (!IS_ERR(srq)) {
		srq->device    	   = pd->device;
		srq->pd        	   = pd;
		srq->uobject       = NULL;
		srq->event_handler = srq_init_attr->event_handler;
		srq->srq_context   = srq_init_attr->srq_context;
		srq->srq_type      = srq_init_attr->srq_type;
		if (srq->srq_type == IB_SRQT_XRC) {
			srq->ext.xrc.xrcd = srq_init_attr->ext.xrc.xrcd;
			srq->ext.xrc.cq   = srq_init_attr->ext.xrc.cq;
			atomic_inc(&srq->ext.xrc.xrcd->usecnt);
			atomic_inc(&srq->ext.xrc.cq->usecnt);
		}
		atomic_inc(&pd->usecnt);
		atomic_set(&srq->usecnt, 0);
	}

	return srq;
}
EXPORT_SYMBOL(ib_create_srq);

int ib_modify_srq(struct ib_srq *srq,
		  struct ib_srq_attr *srq_attr,
		  enum ib_srq_attr_mask srq_attr_mask)
{
	return srq->device->modify_srq ?
		srq->device->modify_srq(srq, srq_attr, srq_attr_mask, NULL) :
		-ENOSYS;
}
EXPORT_SYMBOL(ib_modify_srq);

int ib_query_srq(struct ib_srq *srq,
		 struct ib_srq_attr *srq_attr)
{
	return srq->device->query_srq ?
		srq->device->query_srq(srq, srq_attr) : -ENOSYS;
}
EXPORT_SYMBOL(ib_query_srq);

int ib_destroy_srq(struct ib_srq *srq)
{
	struct ib_pd *pd;
	enum ib_srq_type srq_type;
	struct ib_xrcd *uninitialized_var(xrcd);
	struct ib_cq *uninitialized_var(cq);
	int ret;

	if (atomic_read(&srq->usecnt))
		return -EBUSY;

	pd = srq->pd;
	srq_type = srq->srq_type;
	if (srq_type == IB_SRQT_XRC) {
		xrcd = srq->ext.xrc.xrcd;
		cq = srq->ext.xrc.cq;
	}

	ret = srq->device->destroy_srq(srq);
	if (!ret) {
		atomic_dec(&pd->usecnt);
		if (srq_type == IB_SRQT_XRC) {
			atomic_dec(&xrcd->usecnt);
			atomic_dec(&cq->usecnt);
		}
	}

	return ret;
}
EXPORT_SYMBOL(ib_destroy_srq);

/* Queue pairs */

static void __ib_shared_qp_event_handler(struct ib_event *event, void *context)
{
	struct ib_qp *qp = context;
	unsigned long flags;

	spin_lock_irqsave(&qp->device->event_handler_lock, flags);
	list_for_each_entry(event->element.qp, &qp->open_list, open_list)
		if (event->element.qp->event_handler)
			event->element.qp->event_handler(event, event->element.qp->qp_context);
	spin_unlock_irqrestore(&qp->device->event_handler_lock, flags);
}

static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp)
{
	mutex_lock(&xrcd->tgt_qp_mutex);
	list_add(&qp->xrcd_list, &xrcd->tgt_qp_list);
	mutex_unlock(&xrcd->tgt_qp_mutex);
}

static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp,
				  void (*event_handler)(struct ib_event *, void *),
				  void *qp_context)
{
	struct ib_qp *qp;
	unsigned long flags;

	qp = kzalloc(sizeof *qp, GFP_KERNEL);
	if (!qp)
		return ERR_PTR(-ENOMEM);

	qp->real_qp = real_qp;
	atomic_inc(&real_qp->usecnt);
	qp->device = real_qp->device;
	qp->event_handler = event_handler;
	qp->qp_context = qp_context;
	qp->qp_num = real_qp->qp_num;
	qp->qp_type = real_qp->qp_type;

	spin_lock_irqsave(&real_qp->device->event_handler_lock, flags);
	list_add(&qp->open_list, &real_qp->open_list);
	spin_unlock_irqrestore(&real_qp->device->event_handler_lock, flags);

	return qp;
}

struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd,
			 struct ib_qp_open_attr *qp_open_attr)
{
	struct ib_qp *qp, *real_qp;

	if (qp_open_attr->qp_type != IB_QPT_XRC_TGT)
		return ERR_PTR(-EINVAL);

	qp = ERR_PTR(-EINVAL);
	mutex_lock(&xrcd->tgt_qp_mutex);
	list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) {
		if (real_qp->qp_num == qp_open_attr->qp_num) {
			qp = __ib_open_qp(real_qp, qp_open_attr->event_handler,
					  qp_open_attr->qp_context);
			break;
		}
	}
	mutex_unlock(&xrcd->tgt_qp_mutex);
	return qp;
}
EXPORT_SYMBOL(ib_open_qp);

struct ib_qp *ib_create_qp(struct ib_pd *pd,
			   struct ib_qp_init_attr *qp_init_attr)
{
	struct ib_qp *qp, *real_qp;
	struct ib_device *device;

	device = pd ? pd->device : qp_init_attr->xrcd->device;
	qp = device->create_qp(pd, qp_init_attr, NULL);

	if (!IS_ERR(qp)) {
		qp->device     = device;
		qp->real_qp    = qp;
		qp->uobject    = NULL;
		qp->qp_type    = qp_init_attr->qp_type;

		atomic_set(&qp->usecnt, 0);
		if (qp_init_attr->qp_type == IB_QPT_XRC_TGT) {
			qp->event_handler = __ib_shared_qp_event_handler;
			qp->qp_context = qp;
			qp->pd = NULL;
			qp->send_cq = qp->recv_cq = NULL;
			qp->srq = NULL;
			qp->xrcd = qp_init_attr->xrcd;
			atomic_inc(&qp_init_attr->xrcd->usecnt);
			INIT_LIST_HEAD(&qp->open_list);

			real_qp = qp;
			qp = __ib_open_qp(real_qp, qp_init_attr->event_handler,
					  qp_init_attr->qp_context);
			if (!IS_ERR(qp))
				__ib_insert_xrcd_qp(qp_init_attr->xrcd, real_qp);
			else
				real_qp->device->destroy_qp(real_qp);
		} else {
			qp->event_handler = qp_init_attr->event_handler;
			qp->qp_context = qp_init_attr->qp_context;
			if (qp_init_attr->qp_type == IB_QPT_XRC_INI) {
				qp->recv_cq = NULL;
				qp->srq = NULL;
			} else {
				qp->recv_cq = qp_init_attr->recv_cq;
				atomic_inc(&qp_init_attr->recv_cq->usecnt);
				qp->srq = qp_init_attr->srq;
				if (qp->srq)
					atomic_inc(&qp_init_attr->srq->usecnt);
			}

			qp->pd	    = pd;
			qp->send_cq = qp_init_attr->send_cq;
			qp->xrcd    = NULL;

			atomic_inc(&pd->usecnt);
			atomic_inc(&qp_init_attr->send_cq->usecnt);
		}
	}

	return qp;
}
EXPORT_SYMBOL(ib_create_qp);

static const struct {
	int			valid;
	enum ib_qp_attr_mask	req_param[IB_QPT_MAX];
	enum ib_qp_attr_mask	req_param_add_eth[IB_QPT_MAX];
	enum ib_qp_attr_mask	opt_param[IB_QPT_MAX];
	enum ib_qp_attr_mask	opt_param_add_eth[IB_QPT_MAX];
} qp_state_table[IB_QPS_ERR + 1][IB_QPS_ERR + 1] = {
	[IB_QPS_RESET] = {
		[IB_QPS_RESET] = { .valid = 1 },
		[IB_QPS_INIT]  = {
			.valid = 1,
			.req_param = {
				[IB_QPT_UD]  = (IB_QP_PKEY_INDEX		|
						IB_QP_PORT			|
						IB_QP_QKEY),
				[IB_QPT_RAW_PACKET] = IB_QP_PORT,
				[IB_QPT_UC]  = (IB_QP_PKEY_INDEX		|
						IB_QP_PORT			|
						IB_QP_ACCESS_FLAGS),
				[IB_QPT_RC]  = (IB_QP_PKEY_INDEX		|
						IB_QP_PORT			|
						IB_QP_ACCESS_FLAGS),
				[IB_QPT_XRC_INI] = (IB_QP_PKEY_INDEX		|
						IB_QP_PORT			|
						IB_QP_ACCESS_FLAGS),
				[IB_QPT_XRC_TGT] = (IB_QP_PKEY_INDEX		|
						IB_QP_PORT			|
						IB_QP_ACCESS_FLAGS),
				[IB_QPT_SMI] = (IB_QP_PKEY_INDEX		|
						IB_QP_QKEY),
				[IB_QPT_GSI] = (IB_QP_PKEY_INDEX		|
						IB_QP_QKEY),
			}
		},
	},
	[IB_QPS_INIT]  = {
		[IB_QPS_RESET] = { .valid = 1 },
		[IB_QPS_ERR] =   { .valid = 1 },
		[IB_QPS_INIT]  = {
			.valid = 1,
			.opt_param = {
				[IB_QPT_UD]  = (IB_QP_PKEY_INDEX		|
						IB_QP_PORT			|
						IB_QP_QKEY),
				[IB_QPT_UC]  = (IB_QP_PKEY_INDEX		|
						IB_QP_PORT			|
						IB_QP_ACCESS_FLAGS),
				[IB_QPT_RC]  = (IB_QP_PKEY_INDEX		|
						IB_QP_PORT			|
						IB_QP_ACCESS_FLAGS),
				[IB_QPT_XRC_INI] = (IB_QP_PKEY_INDEX		|
						IB_QP_PORT			|
						IB_QP_ACCESS_FLAGS),
				[IB_QPT_XRC_TGT] = (IB_QP_PKEY_INDEX		|
						IB_QP_PORT			|
						IB_QP_ACCESS_FLAGS),
				[IB_QPT_SMI] = (IB_QP_PKEY_INDEX		|
						IB_QP_QKEY),
				[IB_QPT_GSI] = (IB_QP_PKEY_INDEX		|
						IB_QP_QKEY),
			}
		},
		[IB_QPS_RTR]   = {
			.valid = 1,
			.req_param = {
				[IB_QPT_UC]  = (IB_QP_AV			|
						IB_QP_PATH_MTU			|
						IB_QP_DEST_QPN			|
						IB_QP_RQ_PSN),
				[IB_QPT_RC]  = (IB_QP_AV			|
						IB_QP_PATH_MTU			|
						IB_QP_DEST_QPN			|
						IB_QP_RQ_PSN			|
						IB_QP_MAX_DEST_RD_ATOMIC	|
						IB_QP_MIN_RNR_TIMER),
				[IB_QPT_XRC_INI] = (IB_QP_AV			|
						IB_QP_PATH_MTU			|
						IB_QP_DEST_QPN			|
						IB_QP_RQ_PSN),
				[IB_QPT_XRC_TGT] = (IB_QP_AV			|
						IB_QP_PATH_MTU			|
						IB_QP_DEST_QPN			|
						IB_QP_RQ_PSN			|
						IB_QP_MAX_DEST_RD_ATOMIC	|
						IB_QP_MIN_RNR_TIMER),
			},
			.req_param_add_eth = {
				[IB_QPT_RC]  = (IB_QP_SMAC),
				[IB_QPT_UC]  = (IB_QP_SMAC),
				[IB_QPT_XRC_INI]  = (IB_QP_SMAC),
				[IB_QPT_XRC_TGT]  = (IB_QP_SMAC)
			},
			.opt_param = {
				 [IB_QPT_UD]  = (IB_QP_PKEY_INDEX		|
						 IB_QP_QKEY),
				 [IB_QPT_UC]  = (IB_QP_ALT_PATH			|
						 IB_QP_ACCESS_FLAGS		|
						 IB_QP_PKEY_INDEX),
				 [IB_QPT_RC]  = (IB_QP_ALT_PATH			|
						 IB_QP_ACCESS_FLAGS		|
						 IB_QP_PKEY_INDEX),
				 [IB_QPT_XRC_INI] = (IB_QP_ALT_PATH		|
						 IB_QP_ACCESS_FLAGS		|
						 IB_QP_PKEY_INDEX),
				 [IB_QPT_XRC_TGT] = (IB_QP_ALT_PATH		|
						 IB_QP_ACCESS_FLAGS		|
						 IB_QP_PKEY_INDEX),
				 [IB_QPT_SMI] = (IB_QP_PKEY_INDEX		|
						 IB_QP_QKEY),
				 [IB_QPT_GSI] = (IB_QP_PKEY_INDEX		|
						 IB_QP_QKEY),
			 },
			.opt_param_add_eth = {
				[IB_QPT_RC]  = (IB_QP_ALT_SMAC			|
						IB_QP_VID			|
						IB_QP_ALT_VID),
				[IB_QPT_UC]  = (IB_QP_ALT_SMAC			|
						IB_QP_VID			|
						IB_QP_ALT_VID),
				[IB_QPT_XRC_INI]  = (IB_QP_ALT_SMAC			|
						IB_QP_VID			|
						IB_QP_ALT_VID),
				[IB_QPT_XRC_TGT]  = (IB_QP_ALT_SMAC			|
						IB_QP_VID			|
						IB_QP_ALT_VID)
			}
		}
	},
	[IB_QPS_RTR]   = {
		[IB_QPS_RESET] = { .valid = 1 },
		[IB_QPS_ERR] =   { .valid = 1 },
		[IB_QPS_RTS]   = {
			.valid = 1,
			.req_param = {
				[IB_QPT_UD]  = IB_QP_SQ_PSN,
				[IB_QPT_UC]  = IB_QP_SQ_PSN,
				[IB_QPT_RC]  = (IB_QP_TIMEOUT			|
						IB_QP_RETRY_CNT			|
						IB_QP_RNR_RETRY			|
						IB_QP_SQ_PSN			|
						IB_QP_MAX_QP_RD_ATOMIC),
				[IB_QPT_XRC_INI] = (IB_QP_TIMEOUT		|
						IB_QP_RETRY_CNT			|
						IB_QP_RNR_RETRY			|
						IB_QP_SQ_PSN			|
						IB_QP_MAX_QP_RD_ATOMIC),
				[IB_QPT_XRC_TGT] = (IB_QP_TIMEOUT		|
						IB_QP_SQ_PSN),
				[IB_QPT_SMI] = IB_QP_SQ_PSN,
				[IB_QPT_GSI] = IB_QP_SQ_PSN,
			},
			.opt_param = {
				 [IB_QPT_UD]  = (IB_QP_CUR_STATE		|
						 IB_QP_QKEY),
				 [IB_QPT_UC]  = (IB_QP_CUR_STATE		|
						 IB_QP_ALT_PATH			|
						 IB_QP_ACCESS_FLAGS		|
						 IB_QP_PATH_MIG_STATE),
				 [IB_QPT_RC]  = (IB_QP_CUR_STATE		|
						 IB_QP_ALT_PATH			|
						 IB_QP_ACCESS_FLAGS		|
						 IB_QP_MIN_RNR_TIMER		|
						 IB_QP_PATH_MIG_STATE),
				 [IB_QPT_XRC_INI] = (IB_QP_CUR_STATE		|
						 IB_QP_ALT_PATH			|
						 IB_QP_ACCESS_FLAGS		|
						 IB_QP_PATH_MIG_STATE),
				 [IB_QPT_XRC_TGT] = (IB_QP_CUR_STATE		|
						 IB_QP_ALT_PATH			|
						 IB_QP_ACCESS_FLAGS		|
						 IB_QP_MIN_RNR_TIMER		|
						 IB_QP_PATH_MIG_STATE),
				 [IB_QPT_SMI] = (IB_QP_CUR_STATE		|
						 IB_QP_QKEY),
				 [IB_QPT_GSI] = (IB_QP_CUR_STATE		|
						 IB_QP_QKEY),
			 }
		}
	},
	[IB_QPS_RTS]   = {
		[IB_QPS_RESET] = { .valid = 1 },
		[IB_QPS_ERR] =   { .valid = 1 },
		[IB_QPS_RTS]   = {
			.valid = 1,
			.opt_param = {
				[IB_QPT_UD]  = (IB_QP_CUR_STATE			|
						IB_QP_QKEY),
				[IB_QPT_UC]  = (IB_QP_CUR_STATE			|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_ALT_PATH			|
						IB_QP_PATH_MIG_STATE),
				[IB_QPT_RC]  = (IB_QP_CUR_STATE			|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_ALT_PATH			|
						IB_QP_PATH_MIG_STATE		|
						IB_QP_MIN_RNR_TIMER),
				[IB_QPT_XRC_INI] = (IB_QP_CUR_STATE		|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_ALT_PATH			|
						IB_QP_PATH_MIG_STATE),
				[IB_QPT_XRC_TGT] = (IB_QP_CUR_STATE		|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_ALT_PATH			|
						IB_QP_PATH_MIG_STATE		|
						IB_QP_MIN_RNR_TIMER),
				[IB_QPT_SMI] = (IB_QP_CUR_STATE			|
						IB_QP_QKEY),
				[IB_QPT_GSI] = (IB_QP_CUR_STATE			|
						IB_QP_QKEY),
			}
		},
		[IB_QPS_SQD]   = {
			.valid = 1,
			.opt_param = {
				[IB_QPT_UD]  = IB_QP_EN_SQD_ASYNC_NOTIFY,
				[IB_QPT_UC]  = IB_QP_EN_SQD_ASYNC_NOTIFY,
				[IB_QPT_RC]  = IB_QP_EN_SQD_ASYNC_NOTIFY,
				[IB_QPT_XRC_INI] = IB_QP_EN_SQD_ASYNC_NOTIFY,
				[IB_QPT_XRC_TGT] = IB_QP_EN_SQD_ASYNC_NOTIFY, /* ??? */
				[IB_QPT_SMI] = IB_QP_EN_SQD_ASYNC_NOTIFY,
				[IB_QPT_GSI] = IB_QP_EN_SQD_ASYNC_NOTIFY
			}
		},
	},
	[IB_QPS_SQD]   = {
		[IB_QPS_RESET] = { .valid = 1 },
		[IB_QPS_ERR] =   { .valid = 1 },
		[IB_QPS_RTS]   = {
			.valid = 1,
			.opt_param = {
				[IB_QPT_UD]  = (IB_QP_CUR_STATE			|
						IB_QP_QKEY),
				[IB_QPT_UC]  = (IB_QP_CUR_STATE			|
						IB_QP_ALT_PATH			|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_PATH_MIG_STATE),
				[IB_QPT_RC]  = (IB_QP_CUR_STATE			|
						IB_QP_ALT_PATH			|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_MIN_RNR_TIMER		|
						IB_QP_PATH_MIG_STATE),
				[IB_QPT_XRC_INI] = (IB_QP_CUR_STATE		|
						IB_QP_ALT_PATH			|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_PATH_MIG_STATE),
				[IB_QPT_XRC_TGT] = (IB_QP_CUR_STATE		|
						IB_QP_ALT_PATH			|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_MIN_RNR_TIMER		|
						IB_QP_PATH_MIG_STATE),
				[IB_QPT_SMI] = (IB_QP_CUR_STATE			|
						IB_QP_QKEY),
				[IB_QPT_GSI] = (IB_QP_CUR_STATE			|
						IB_QP_QKEY),
			}
		},
		[IB_QPS_SQD]   = {
			.valid = 1,
			.opt_param = {
				[IB_QPT_UD]  = (IB_QP_PKEY_INDEX		|
						IB_QP_QKEY),
				[IB_QPT_UC]  = (IB_QP_AV			|
						IB_QP_ALT_PATH			|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_PKEY_INDEX		|
						IB_QP_PATH_MIG_STATE),
				[IB_QPT_RC]  = (IB_QP_PORT			|
						IB_QP_AV			|
						IB_QP_TIMEOUT			|
						IB_QP_RETRY_CNT			|
						IB_QP_RNR_RETRY			|
						IB_QP_MAX_QP_RD_ATOMIC		|
						IB_QP_MAX_DEST_RD_ATOMIC	|
						IB_QP_ALT_PATH			|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_PKEY_INDEX		|
						IB_QP_MIN_RNR_TIMER		|
						IB_QP_PATH_MIG_STATE),
				[IB_QPT_XRC_INI] = (IB_QP_PORT			|
						IB_QP_AV			|
						IB_QP_TIMEOUT			|
						IB_QP_RETRY_CNT			|
						IB_QP_RNR_RETRY			|
						IB_QP_MAX_QP_RD_ATOMIC		|
						IB_QP_ALT_PATH			|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_PKEY_INDEX		|
						IB_QP_PATH_MIG_STATE),
				[IB_QPT_XRC_TGT] = (IB_QP_PORT			|
						IB_QP_AV			|
						IB_QP_TIMEOUT			|
						IB_QP_MAX_DEST_RD_ATOMIC	|
						IB_QP_ALT_PATH			|
						IB_QP_ACCESS_FLAGS		|
						IB_QP_PKEY_INDEX		|
						IB_QP_MIN_RNR_TIMER		|
						IB_QP_PATH_MIG_STATE),
				[IB_QPT_SMI] = (IB_QP_PKEY_INDEX		|
						IB_QP_QKEY),
				[IB_QPT_GSI] = (IB_QP_PKEY_INDEX		|
						IB_QP_QKEY),
			}
		}
	},
	[IB_QPS_SQE]   = {
		[IB_QPS_RESET] = { .valid = 1 },
		[IB_QPS_ERR] =   { .valid = 1 },
		[IB_QPS_RTS]   = {
			.valid = 1,
			.opt_param = {
				[IB_QPT_UD]  = (IB_QP_CUR_STATE			|
						IB_QP_QKEY),
				[IB_QPT_UC]  = (IB_QP_CUR_STATE			|
						IB_QP_ACCESS_FLAGS),
				[IB_QPT_SMI] = (IB_QP_CUR_STATE			|
						IB_QP_QKEY),
				[IB_QPT_GSI] = (IB_QP_CUR_STATE			|
						IB_QP_QKEY),
			}
		}
	},
	[IB_QPS_ERR] = {
		[IB_QPS_RESET] = { .valid = 1 },
		[IB_QPS_ERR] =   { .valid = 1 }
	}
};

int ib_modify_qp_is_ok(enum ib_qp_state cur_state, enum ib_qp_state next_state,
		       enum ib_qp_type type, enum ib_qp_attr_mask mask,
		       enum rdma_link_layer ll)
{
	enum ib_qp_attr_mask req_param, opt_param;

	if (cur_state  < 0 || cur_state  > IB_QPS_ERR ||
	    next_state < 0 || next_state > IB_QPS_ERR)
		return 0;

	if (mask & IB_QP_CUR_STATE  &&
	    cur_state != IB_QPS_RTR && cur_state != IB_QPS_RTS &&
	    cur_state != IB_QPS_SQD && cur_state != IB_QPS_SQE)
		return 0;

	if (!qp_state_table[cur_state][next_state].valid)
		return 0;

	req_param = qp_state_table[cur_state][next_state].req_param[type];
	opt_param = qp_state_table[cur_state][next_state].opt_param[type];

	if (ll == IB_LINK_LAYER_ETHERNET) {
		req_param |= qp_state_table[cur_state][next_state].
			req_param_add_eth[type];
		opt_param |= qp_state_table[cur_state][next_state].
			opt_param_add_eth[type];
	}

	if ((mask & req_param) != req_param)
		return 0;

	if (mask & ~(req_param | opt_param | IB_QP_STATE))
		return 0;

	return 1;
}
EXPORT_SYMBOL(ib_modify_qp_is_ok);

int ib_modify_qp(struct ib_qp *qp,
		 struct ib_qp_attr *qp_attr,
		 int qp_attr_mask)
{
	return qp->device->modify_qp(qp->real_qp, qp_attr, qp_attr_mask, NULL);
}
EXPORT_SYMBOL(ib_modify_qp);

int ib_query_qp(struct ib_qp *qp,
		struct ib_qp_attr *qp_attr,
		int qp_attr_mask,
		struct ib_qp_init_attr *qp_init_attr)
{
	return qp->device->query_qp ?
		qp->device->query_qp(qp->real_qp, qp_attr, qp_attr_mask, qp_init_attr) :
		-ENOSYS;
}
EXPORT_SYMBOL(ib_query_qp);

int ib_close_qp(struct ib_qp *qp)
{
	struct ib_qp *real_qp;
	unsigned long flags;

	real_qp = qp->real_qp;
	if (real_qp == qp)
		return -EINVAL;

	spin_lock_irqsave(&real_qp->device->event_handler_lock, flags);
	list_del(&qp->open_list);
	spin_unlock_irqrestore(&real_qp->device->event_handler_lock, flags);

	atomic_dec(&real_qp->usecnt);
	kfree(qp);

	return 0;
}
EXPORT_SYMBOL(ib_close_qp);

static int __ib_destroy_shared_qp(struct ib_qp *qp)
{
	struct ib_xrcd *xrcd;
	struct ib_qp *real_qp;
	int ret;

	real_qp = qp->real_qp;
	xrcd = real_qp->xrcd;

	mutex_lock(&xrcd->tgt_qp_mutex);
	ib_close_qp(qp);
	if (atomic_read(&real_qp->usecnt) == 0)
		list_del(&real_qp->xrcd_list);
	else
		real_qp = NULL;
	mutex_unlock(&xrcd->tgt_qp_mutex);

	if (real_qp) {
		ret = ib_destroy_qp(real_qp);
		if (!ret)
			atomic_dec(&xrcd->usecnt);
		else
			__ib_insert_xrcd_qp(xrcd, real_qp);
	}

	return 0;
}

int ib_destroy_qp(struct ib_qp *qp)
{
	struct ib_pd *pd;
	struct ib_cq *scq, *rcq;
	struct ib_srq *srq;
	int ret;

	if (atomic_read(&qp->usecnt))
		return -EBUSY;

	if (qp->real_qp != qp)
		return __ib_destroy_shared_qp(qp);

	pd   = qp->pd;
	scq  = qp->send_cq;
	rcq  = qp->recv_cq;
	srq  = qp->srq;

	ret = qp->device->destroy_qp(qp);
	if (!ret) {
		if (pd)
			atomic_dec(&pd->usecnt);
		if (scq)
			atomic_dec(&scq->usecnt);
		if (rcq)
			atomic_dec(&rcq->usecnt);
		if (srq)
			atomic_dec(&srq->usecnt);
	}

	return ret;
}
EXPORT_SYMBOL(ib_destroy_qp);

/* Completion queues */

struct ib_cq *ib_create_cq(struct ib_device *device,
			   ib_comp_handler comp_handler,
			   void (*event_handler)(struct ib_event *, void *),
			   void *cq_context, int cqe, int comp_vector)
{
	struct ib_cq *cq;

	cq = device->create_cq(device, cqe, comp_vector, NULL, NULL);

	if (!IS_ERR(cq)) {
		cq->device        = device;
		cq->uobject       = NULL;
		cq->comp_handler  = comp_handler;
		cq->event_handler = event_handler;
		cq->cq_context    = cq_context;
		atomic_set(&cq->usecnt, 0);
	}

	return cq;
}
EXPORT_SYMBOL(ib_create_cq);

int ib_modify_cq(struct ib_cq *cq, u16 cq_count, u16 cq_period)
{
	return cq->device->modify_cq ?
		cq->device->modify_cq(cq, cq_count, cq_period) : -ENOSYS;
}
EXPORT_SYMBOL(ib_modify_cq);

int ib_destroy_cq(struct ib_cq *cq)
{
	if (atomic_read(&cq->usecnt))
		return -EBUSY;

	return cq->device->destroy_cq(cq);
}
EXPORT_SYMBOL(ib_destroy_cq);

int ib_resize_cq(struct ib_cq *cq, int cqe)
{
	return cq->device->resize_cq ?
		cq->device->resize_cq(cq, cqe, NULL) : -ENOSYS;
}
EXPORT_SYMBOL(ib_resize_cq);

/* Memory regions */

struct ib_mr *ib_get_dma_mr(struct ib_pd *pd, int mr_access_flags)
{
	struct ib_mr *mr;
	int err;

	err = ib_check_mr_access(mr_access_flags);
	if (err)
		return ERR_PTR(err);

	mr = pd->device->get_dma_mr(pd, mr_access_flags);

	if (!IS_ERR(mr)) {
		mr->device  = pd->device;
		mr->pd      = pd;
		mr->uobject = NULL;
		atomic_inc(&pd->usecnt);
		atomic_set(&mr->usecnt, 0);
	}

	return mr;
}
EXPORT_SYMBOL(ib_get_dma_mr);

struct ib_mr *ib_reg_phys_mr(struct ib_pd *pd,
			     struct ib_phys_buf *phys_buf_array,
			     int num_phys_buf,
			     int mr_access_flags,
			     u64 *iova_start)
{
	struct ib_mr *mr;
	int err;

	err = ib_check_mr_access(mr_access_flags);
	if (err)
		return ERR_PTR(err);

	if (!pd->device->reg_phys_mr)
		return ERR_PTR(-ENOSYS);

	mr = pd->device->reg_phys_mr(pd, phys_buf_array, num_phys_buf,
				     mr_access_flags, iova_start);

	if (!IS_ERR(mr)) {
		mr->device  = pd->device;
		mr->pd      = pd;
		mr->uobject = NULL;
		atomic_inc(&pd->usecnt);
		atomic_set(&mr->usecnt, 0);
	}

	return mr;
}
EXPORT_SYMBOL(ib_reg_phys_mr);

int ib_rereg_phys_mr(struct ib_mr *mr,
		     int mr_rereg_mask,
		     struct ib_pd *pd,
		     struct ib_phys_buf *phys_buf_array,
		     int num_phys_buf,
		     int mr_access_flags,
		     u64 *iova_start)
{
	struct ib_pd *old_pd;
	int ret;

	ret = ib_check_mr_access(mr_access_flags);
	if (ret)
		return ret;

	if (!mr->device->rereg_phys_mr)
		return -ENOSYS;

	if (atomic_read(&mr->usecnt))
		return -EBUSY;

	old_pd = mr->pd;

	ret = mr->device->rereg_phys_mr(mr, mr_rereg_mask, pd,
					phys_buf_array, num_phys_buf,
					mr_access_flags, iova_start);

	if (!ret && (mr_rereg_mask & IB_MR_REREG_PD)) {
		atomic_dec(&old_pd->usecnt);
		atomic_inc(&pd->usecnt);
	}

	return ret;
}
EXPORT_SYMBOL(ib_rereg_phys_mr);

int ib_query_mr(struct ib_mr *mr, struct ib_mr_attr *mr_attr)
{
	return mr->device->query_mr ?
		mr->device->query_mr(mr, mr_attr) : -ENOSYS;
}
EXPORT_SYMBOL(ib_query_mr);

int ib_dereg_mr(struct ib_mr *mr)
{
	struct ib_pd *pd;
	int ret;

	if (atomic_read(&mr->usecnt))
		return -EBUSY;

	pd = mr->pd;
	ret = mr->device->dereg_mr(mr);
	if (!ret)
		atomic_dec(&pd->usecnt);

	return ret;
}
EXPORT_SYMBOL(ib_dereg_mr);

struct ib_mr *ib_alloc_fast_reg_mr(struct ib_pd *pd, int max_page_list_len)
{
	struct ib_mr *mr;

	if (!pd->device->alloc_fast_reg_mr)
		return ERR_PTR(-ENOSYS);

	mr = pd->device->alloc_fast_reg_mr(pd, max_page_list_len);

	if (!IS_ERR(mr)) {
		mr->device  = pd->device;
		mr->pd      = pd;
		mr->uobject = NULL;
		atomic_inc(&pd->usecnt);
		atomic_set(&mr->usecnt, 0);
	}

	return mr;
}
EXPORT_SYMBOL(ib_alloc_fast_reg_mr);

struct ib_fast_reg_page_list *ib_alloc_fast_reg_page_list(struct ib_device *device,
							  int max_page_list_len)
{
	struct ib_fast_reg_page_list *page_list;

	if (!device->alloc_fast_reg_page_list)
		return ERR_PTR(-ENOSYS);

	page_list = device->alloc_fast_reg_page_list(device, max_page_list_len);

	if (!IS_ERR(page_list)) {
		page_list->device = device;
		page_list->max_page_list_len = max_page_list_len;
	}

	return page_list;
}
EXPORT_SYMBOL(ib_alloc_fast_reg_page_list);

void ib_free_fast_reg_page_list(struct ib_fast_reg_page_list *page_list)
{
	page_list->device->free_fast_reg_page_list(page_list);
}
EXPORT_SYMBOL(ib_free_fast_reg_page_list);

/* Memory windows */

struct ib_mw *ib_alloc_mw(struct ib_pd *pd, enum ib_mw_type type)
{
	struct ib_mw *mw;

	if (!pd->device->alloc_mw)
		return ERR_PTR(-ENOSYS);

	mw = pd->device->alloc_mw(pd, type);
	if (!IS_ERR(mw)) {
		mw->device  = pd->device;
		mw->pd      = pd;
		mw->uobject = NULL;
		mw->type    = type;
		atomic_inc(&pd->usecnt);
	}

	return mw;
}
EXPORT_SYMBOL(ib_alloc_mw);

int ib_dealloc_mw(struct ib_mw *mw)
{
	struct ib_pd *pd;
	int ret;

	pd = mw->pd;
	ret = mw->device->dealloc_mw(mw);
	if (!ret)
		atomic_dec(&pd->usecnt);

	return ret;
}
EXPORT_SYMBOL(ib_dealloc_mw);

/* "Fast" memory regions */

struct ib_fmr *ib_alloc_fmr(struct ib_pd *pd,
			    int mr_access_flags,
			    struct ib_fmr_attr *fmr_attr)
{
	struct ib_fmr *fmr;

	if (!pd->device->alloc_fmr)
		return ERR_PTR(-ENOSYS);

	fmr = pd->device->alloc_fmr(pd, mr_access_flags, fmr_attr);
	if (!IS_ERR(fmr)) {
		fmr->device = pd->device;
		fmr->pd     = pd;
		atomic_inc(&pd->usecnt);
	}

	return fmr;
}
EXPORT_SYMBOL(ib_alloc_fmr);

int ib_unmap_fmr(struct list_head *fmr_list)
{
	struct ib_fmr *fmr;

	if (list_empty(fmr_list))
		return 0;

	fmr = list_entry(fmr_list->next, struct ib_fmr, list);
	return fmr->device->unmap_fmr(fmr_list);
}
EXPORT_SYMBOL(ib_unmap_fmr);

int ib_dealloc_fmr(struct ib_fmr *fmr)
{
	struct ib_pd *pd;
	int ret;

	pd = fmr->pd;
	ret = fmr->device->dealloc_fmr(fmr);
	if (!ret)
		atomic_dec(&pd->usecnt);

	return ret;
}
EXPORT_SYMBOL(ib_dealloc_fmr);

/* Multicast groups */

int ib_attach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid)
{
	int ret;

	if (!qp->device->attach_mcast)
		return -ENOSYS;
	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD)
		return -EINVAL;

	ret = qp->device->attach_mcast(qp, gid, lid);
	if (!ret)
		atomic_inc(&qp->usecnt);
	return ret;
}
EXPORT_SYMBOL(ib_attach_mcast);

int ib_detach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid)
{
	int ret;

	if (!qp->device->detach_mcast)
		return -ENOSYS;
	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD)
		return -EINVAL;

	ret = qp->device->detach_mcast(qp, gid, lid);
	if (!ret)
		atomic_dec(&qp->usecnt);
	return ret;
}
EXPORT_SYMBOL(ib_detach_mcast);

struct ib_xrcd *ib_alloc_xrcd(struct ib_device *device)
{
	struct ib_xrcd *xrcd;

	if (!device->alloc_xrcd)
		return ERR_PTR(-ENOSYS);

	xrcd = device->alloc_xrcd(device, NULL, NULL);
	if (!IS_ERR(xrcd)) {
		xrcd->device = device;
		xrcd->inode = NULL;
		atomic_set(&xrcd->usecnt, 0);
		mutex_init(&xrcd->tgt_qp_mutex);
		INIT_LIST_HEAD(&xrcd->tgt_qp_list);
	}

	return xrcd;
}
EXPORT_SYMBOL(ib_alloc_xrcd);

int ib_dealloc_xrcd(struct ib_xrcd *xrcd)
{
	struct ib_qp *qp;
	int ret;

	if (atomic_read(&xrcd->usecnt))
		return -EBUSY;

	while (!list_empty(&xrcd->tgt_qp_list)) {
		qp = list_entry(xrcd->tgt_qp_list.next, struct ib_qp, xrcd_list);
		ret = ib_destroy_qp(qp);
		if (ret)
			return ret;
	}

	return xrcd->device->dealloc_xrcd(xrcd);
}
EXPORT_SYMBOL(ib_dealloc_xrcd);

struct ib_flow *ib_create_flow(struct ib_qp *qp,
			       struct ib_flow_attr *flow_attr,
			       int domain)
{
	struct ib_flow *flow_id;
	if (!qp->device->create_flow)
		return ERR_PTR(-ENOSYS);

	flow_id = qp->device->create_flow(qp, flow_attr, domain);
	if (!IS_ERR(flow_id))
		atomic_inc(&qp->usecnt);
	return flow_id;
}
EXPORT_SYMBOL(ib_create_flow);

int ib_destroy_flow(struct ib_flow *flow_id)
{
	int err;
	struct ib_qp *qp = flow_id->qp;

	err = qp->device->destroy_flow(flow_id);
	if (!err)
		atomic_dec(&qp->usecnt);
	return err;
}
EXPORT_SYMBOL(ib_destroy_flow);