path: root/drivers/infiniband/core/multicast.c

/*
 * Copyright (c) 2006 Intel Corporation.  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/completion.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/bitops.h>
#include <linux/random.h>

#include <rdma/ib_cache.h>
#include "sa.h"

static int mcast_add_one(struct ib_device *device);
static void mcast_remove_one(struct ib_device *device, void *client_data);

static struct ib_client mcast_client = {
	.name   = "ib_multicast",
	.add    = mcast_add_one,
	.remove = mcast_remove_one
};

static struct ib_sa_client	sa_client;
static struct workqueue_struct	*mcast_wq;
static union ib_gid mgid0;

struct mcast_device;

struct mcast_port {
	struct mcast_device	*dev;
	spinlock_t		lock;
	struct rb_root		table;
	refcount_t		refcount;
	struct completion	comp;
	u32			port_num;
};

struct mcast_device {
	struct ib_device	*device;
	struct ib_event_handler	event_handler;
	int			start_port;
	int			end_port;
	struct mcast_port	port[];
};

enum mcast_state {
	MCAST_JOINING,
	MCAST_MEMBER,
	MCAST_ERROR,
};

enum mcast_group_state {
	MCAST_IDLE,
	MCAST_BUSY,
	MCAST_GROUP_ERROR,
	MCAST_PKEY_EVENT
};

enum {
	MCAST_INVALID_PKEY_INDEX = 0xFFFF
};

struct mcast_member;

struct mcast_group {
	struct ib_sa_mcmember_rec rec;
	struct rb_node		node;
	struct mcast_port	*port;
	spinlock_t		lock;
	struct work_struct	work;
	struct list_head	pending_list;
	struct list_head	active_list;
	struct mcast_member	*last_join;
	int			members[NUM_JOIN_MEMBERSHIP_TYPES];
	atomic_t		refcount;
	enum mcast_group_state	state;
	struct ib_sa_query	*query;
	u16			pkey_index;
	u8			leave_state;
	int			retries;
};

struct mcast_member {
	struct ib_sa_multicast	multicast;
	struct ib_sa_client	*client;
	struct mcast_group	*group;
	struct list_head	list;
	enum mcast_state	state;
	refcount_t		refcount;
	struct completion	comp;
};

static void join_handler(int status, struct ib_sa_mcmember_rec *rec,
			 void *context);
static void leave_handler(int status, struct ib_sa_mcmember_rec *rec,
			  void *context);

static struct mcast_group *mcast_find(struct mcast_port *port,
				      union ib_gid *mgid)
{
	struct rb_node *node = port->table.rb_node;
	struct mcast_group *group;
	int ret;

	while (node) {
		group = rb_entry(node, struct mcast_group, node);
		ret = memcmp(mgid->raw, group->rec.mgid.raw, sizeof *mgid);
		if (!ret)
			return group;

		if (ret < 0)
			node = node->rb_left;
		else
			node = node->rb_right;
	}
	return NULL;
}

static struct mcast_group *mcast_insert(struct mcast_port *port,
					struct mcast_group *group,
					int allow_duplicates)
{
	struct rb_node **link = &port->table.rb_node;
	struct rb_node *parent = NULL;
	struct mcast_group *cur_group;
	int ret;

	while (*link) {
		parent = *link;
		cur_group = rb_entry(parent, struct mcast_group, node);

		ret = memcmp(group->rec.mgid.raw, cur_group->rec.mgid.raw,
			     sizeof group->rec.mgid);
		if (ret < 0)
			link = &(*link)->rb_left;
		else if (ret > 0)
			link = &(*link)->rb_right;
		else if (allow_duplicates)
			link = &(*link)->rb_left;
		else
			return cur_group;
	}
	rb_link_node(&group->node, parent, link);
	rb_insert_color(&group->node, &port->table);
	return