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/*
* Copyright (c) 2006 Oracle. 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/in.h>
#include "rds.h"
#include "loop.h"
static struct rds_transport *transports[RDS_TRANS_COUNT];
static DECLARE_RWSEM(rds_trans_sem);
int rds_trans_register(struct rds_transport *trans)
{
BUG_ON(strlen(trans->t_name) + 1 > TRANSNAMSIZ);
down_write(&rds_trans_sem);
if (transports[trans->t_type])
printk(KERN_ERR "RDS Transport type %d already registered\n",
trans->t_type);
else {
transports[trans->t_type] = trans;
printk(KERN_INFO "Registered RDS/%s transport\n", trans->t_name);
}
up_write(&rds_trans_sem);
return 0;
}
EXPORT_SYMBOL_GPL(rds_trans_register);
void rds_trans_unregister(struct rds_transport *trans)
{
down_write(&rds_trans_sem);
transports[trans->t_type] = NULL;
printk(KERN_INFO "Unregistered RDS/%s transport\n", trans->t_name);
up_write(&rds_trans_sem);
}
EXPORT_SYMBOL_GPL(rds_trans_unregister);
void rds_trans_put(struct rds_transport *trans)
{
if (trans && trans->t_owner)
module_put(trans->t_owner);
}
struct rds_transport *rds_trans_get_preferred(__be32 addr)
{
struct rds_transport *ret = NULL;
struct rds_transport *trans;
unsigned int i;
if (IN_LOOPBACK(ntohl(addr)))
return &rds_loop_transport;
down_read(&rds_trans_sem);
for (i = 0; i < RDS_TRANS_COUNT; i++) {
trans = transports[i];
if (trans && (trans->laddr_check(addr) == 0) &&
(!trans->t_owner || try_module_get(trans->t_owner))) {
ret = trans;
break;
}
}
up_read(&rds_trans_sem);
return ret;
}
/*
* This returns the number of stats entries in the snapshot and only
* copies them using the iter if there is enough space for them. The
* caller passes in the global stats so that we can size and copy while
* holding the lock.
*/
unsigned int rds_trans_stats_info_copy(struct rds_info_iterator *iter,
unsigned int avail)
{
struct rds_transport *trans;
unsigned int total = 0;
unsigned int part;
int i;
rds_info_iter_unmap(iter);
down_read(&rds_trans_sem);
for (i = 0; i < RDS_TRANS_COUNT; i++)
{
trans = transports[i];
if (!trans || !trans->stats_info_copy)
continue;
part = trans->stats_info_copy(iter, avail);
avail -= min(avail, part);
total += part;
}
up_read(&rds_trans_sem);
return total;
}
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