/* * 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) module_put(trans->t_owner); } struct rds_transport *rds_trans_get_preferred(struct net *net, __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(net, addr) == 0) && (!trans->t_owner || try_module_get(trans->t_owner))) { ret = trans; break; } } up_read(&rds_trans_sem); return ret; } struct rds_transport *rds_trans_get(int t_type) { struct rds_transport *ret = NULL; struct rds_transport *trans; unsigned int i; down_read(&rds_trans_sem); for (i = 0; i < RDS_TRANS_COUNT; i++) { trans = transports[i]; if (trans && trans->t_type == t_type && (!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; }