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-rw-r--r--net/rds/transport.c169
1 files changed, 169 insertions, 0 deletions
diff --git a/net/rds/transport.c b/net/rds/transport.c
new file mode 100644
index 000000000..f8001ec80
--- /dev/null
+++ b/net/rds/transport.c
@@ -0,0 +1,169 @@
+/*
+ * Copyright (c) 2006, 2017 Oracle and/or its affiliates. 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 <linux/ipv6.h>
+
+#include "rds.h"
+#include "loop.h"
+
+static char * const rds_trans_modules[] = {
+ [RDS_TRANS_IB] = "rds_rdma",
+ [RDS_TRANS_GAP] = NULL,
+ [RDS_TRANS_TCP] = "rds_tcp",
+};
+
+static struct rds_transport *transports[RDS_TRANS_COUNT];
+static DECLARE_RWSEM(rds_trans_sem);
+
+void 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);
+}
+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,
+ const struct in6_addr *addr,
+ __u32 scope_id)
+{
+ struct rds_transport *ret = NULL;
+ struct rds_transport *trans;
+ unsigned int i;
+
+ if (ipv6_addr_v4mapped(addr)) {
+ if (*(u_int8_t *)&addr->s6_addr32[3] == IN_LOOPBACKNET)
+ return &rds_loop_transport;
+ } else if (ipv6_addr_loopback(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, scope_id) == 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;
+
+ down_read(&rds_trans_sem);
+ trans = transports[t_type];
+ if (!trans) {
+ up_read(&rds_trans_sem);
+ if (rds_trans_modules[t_type])
+ request_module(rds_trans_modules[t_type]);
+ down_read(&rds_trans_sem);
+ trans = transports[t_type];
+ }
+ if (trans && trans->t_type == t_type &&
+ (!trans->t_owner || try_module_get(trans->t_owner)))
+ ret = trans;
+
+ 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;
+}