/* * 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 <net/sock.h> #include <linux/in.h> #include <linux/if_arp.h> #include <linux/jhash.h> #include <linux/ratelimit.h> #include "rds.h" #define BIND_HASH_SIZE 1024 static struct hlist_head bind_hash_table[BIND_HASH_SIZE]; static DEFINE_SPINLOCK(rds_bind_lock); static struct hlist_head *hash_to_bucket(__be32 addr, __be16 port) { return bind_hash_table + (jhash_2words((u32)addr, (u32)port, 0) & (BIND_HASH_SIZE - 1)); } static struct rds_sock *rds_bind_lookup(__be32 addr, __be16 port, struct rds_sock *insert) { struct rds_sock *rs; struct hlist_head *head = hash_to_bucket(addr, port); u64 cmp; u64 needle = ((u64)be32_to_cpu(addr) << 32) | be16_to_cpu(port); rcu_read_lock(); hlist_for_each_entry_rcu(rs, head, rs_bound_node) { cmp = ((u64)be32_to_cpu(rs->rs_bound_addr) << 32) | be16_to_cpu(rs->rs_bound_port); if (cmp == needle) { rcu_read_unlock(); return rs; } } rcu_read_unlock(); if (insert) { /* * make sure our addr and port are set before * we are added to the list, other people * in rcu will find us as soon as the * hlist_add_head_rcu is done */ insert->rs_bound_addr = addr; insert->rs_bound_port = port; rds_sock_addref(insert); hlist_add_head_rcu(&insert->rs_bound_node, head); } return NULL; } /* * Return the rds_sock bound at the given local address. * * The rx path can race with rds_release. We notice if rds_release() has * marked this socket and don't return a rs ref to the rx path. */ struct rds_sock *rds_find_bound(__be32 addr, __be16 port) { struct rds_sock *rs; rs = rds_bind_lookup(addr, port, NULL); if (rs && !sock_flag(rds_rs_to_sk(rs), SOCK_DEAD)) rds_sock_addref(rs); else rs = NULL; rdsdebug("returning rs %p for %pI4:%u\n", rs, &addr, ntohs(port)); return rs; } /* returns -ve errno or +ve port */ static int rds_add_bound(struct rds_sock *rs, __be32 addr, __be16 *port) { unsigned long flags; int ret = -EADDRINUSE; u16 rover, last; if (*port != 0) { rover = be16_to_cpu(*port); last = rover; } else { rover = max_t(u16, prandom_u32(), 2); last = rover - 1; } spin_lock_irqsave(&rds_bind_lock, flags); do { if (rover == 0) rover++; if (!rds_bind_lookup(addr, cpu_to_be16(rover), rs)) { *port = rs->rs_bound_port; ret = 0; rdsdebug("rs %p binding to %pI4:%d\n", rs, &addr, (int)ntohs(*port)); break; } } while (rover++ != last); spin_unlock_irqrestore(&rds_bind_lock, flags); return ret; } void rds_remove_bound(struct rds_sock *rs) { unsigned long flags; spin_lock_irqsave(&rds_bind_lock, flags); if (rs->rs_bound_addr) { rdsdebug("rs %p unbinding from %pI4:%d\n", rs, &rs->rs_bound_addr, ntohs(rs->rs_bound_port)); hlist_del_init_rcu(&rs->rs_bound_node); rds_sock_put(rs); rs->rs_bound_addr = 0; } spin_unlock_irqrestore(&rds_bind_lock, flags); } int rds_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) { struct sock *sk = sock->sk; struct sockaddr_in *sin = (struct sockaddr_in *)uaddr; struct rds_sock *rs = rds_sk_to_rs(sk); struct rds_transport *trans; int ret = 0; lock_sock(sk); if (addr_len != sizeof(struct sockaddr_in) || sin->sin_family != AF_INET || rs->rs_bound_addr || sin->sin_addr.s_addr == htonl(INADDR_ANY)) { ret = -EINVAL; goto out; } ret = rds_add_bound(rs, sin->sin_addr.s_addr, &sin->sin_port); if (ret) goto out; if (rs->rs_transport) { /* previously bound */ ret = 0; goto out; } trans = rds_trans_get_preferred(sock_net(sock->sk), sin->sin_addr.s_addr); if (!trans) { ret = -EADDRNOTAVAIL; rds_remove_bound(rs); printk_ratelimited(KERN_INFO "RDS: rds_bind() could not find a transport, " "load rds_tcp or rds_rdma?\n"); goto out; } rs->rs_transport = trans; ret = 0; out: release_sock(sk); /* we might have called rds_remove_bound on error */ if (ret) synchronize_rcu(); return ret; }