path: root/drivers/infiniband/ulp/iser/iser_verbs.c

/*
 * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
 * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
 * Copyright (c) 2013-2014 Mellanox Technologies. 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/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/delay.h>

#include "iscsi_iser.h"

#define ISCSI_ISER_MAX_CONN	8
#define ISER_MAX_RX_LEN		(ISER_QP_MAX_RECV_DTOS * ISCSI_ISER_MAX_CONN)
#define ISER_MAX_TX_LEN		(ISER_QP_MAX_REQ_DTOS  * ISCSI_ISER_MAX_CONN)
#define ISER_MAX_CQ_LEN		(ISER_MAX_RX_LEN + ISER_MAX_TX_LEN + \
				 ISCSI_ISER_MAX_CONN)

static void iser_qp_event_callback(struct ib_event *cause, void *context)
{
	iser_err("qp event %s (%d)\n",
		 ib_event_msg(cause->event), cause->event);
}

static void iser_event_handler(struct ib_event_handler *handler,
				struct ib_event *event)
{
	iser_err("async event %s (%d) on device %s port %d\n",
		 ib_event_msg(event->event), event->event,
		dev_name(&event->device->dev), event->element.port_num);
}

/**
 * iser_create_device_ib_res - creates Protection Domain (PD), Completion
 * Queue (CQ), DMA Memory Region (DMA MR) with the device associated with
 * the adapator.
 *
 * returns 0 on success, -1 on failure
 */
static int iser_create_device_ib_res(struct iser_device *device)
{
	struct ib_device *ib_dev = device->ib_device;
	int ret, i, max_cqe;

	ret = iser_assign_reg_ops(device);
	if (ret)
		return ret;

	device->comps_used = min_t(int, num_online_cpus(),
				 ib_dev->num_comp_vectors);

	device->comps = kcalloc(device->comps_used, sizeof(*device->comps),
				GFP_KERNEL);
	if (!device->comps)
		goto comps_err;

	max_cqe = min(ISER_MAX_CQ_LEN, ib_dev->attrs.max_cqe);

	iser_info("using %d CQs, device %s supports %d vectors max_cqe %d\n",
		  device->comps_used, dev_name(&ib_dev->dev),
		  ib_dev->num_comp_vectors, max_cqe);

	device->pd = ib_alloc_pd(ib_dev,
		iser_always_reg ? 0 : IB_PD_UNSAFE_GLOBAL_RKEY);
	if (IS_ERR(device->pd))
		goto pd_err;

	for (i = 0; i < device->comps_used; i++) {
		struct iser_comp *comp = &device->comps[i];

		comp->cq = ib_alloc_cq(ib_dev, comp, max_cqe, i,
				       IB_POLL_SOFTIRQ);
		if (IS_ERR(comp->cq)) {
			comp->cq = NULL;
			goto cq_err;
		}
	}

	INIT_IB_EVENT_HANDLER(&device->event_handler, ib_dev,
			      iser_event_handler);
	ib_register_event_handler(&device->event_handler);
	return 0;

cq_err:
	for (i = 0; i < device->comps_used; i++) {
		struct iser_comp *comp = &device->comps[i];

		if (comp->cq)
			ib_free_cq(comp->cq);
	}
	ib_dealloc_pd(device->pd);
pd_err:
	kfree(device->comps);
comps_err:
	iser_err("failed to allocate an IB resource\n");
	return -1;
}

/**
 * iser_free_device_ib_res - destroy/dealloc/dereg the DMA MR,
 * CQ and PD created with the device associated with the adapator.
 */
static void iser_free_device_ib_res(struct iser_device *device)
{
	int i;

	for (i = 0; i < device->comps_used; i++