diff options
author | Paul Mackerras <paulus@samba.org> | 2007-04-30 12:38:01 +1000 |
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committer | Paul Mackerras <paulus@samba.org> | 2007-04-30 12:38:01 +1000 |
commit | 49e1900d4cc2e7bcecb681fe60f0990bec2dcce8 (patch) | |
tree | 253801ebf57e0a23856a2c7be129c2c178f62fdf /net/rxrpc/ar-local.c | |
parent | 34f6d749c0a328817d5e36274e53121c1db734dc (diff) | |
parent | b9099ff63c75216d6ca10bce5a1abcd9293c27e6 (diff) |
Merge branch 'linux-2.6' into for-2.6.22
Diffstat (limited to 'net/rxrpc/ar-local.c')
-rw-r--r-- | net/rxrpc/ar-local.c | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/net/rxrpc/ar-local.c b/net/rxrpc/ar-local.c new file mode 100644 index 00000000000..fe03f71f17d --- /dev/null +++ b/net/rxrpc/ar-local.c @@ -0,0 +1,309 @@ +/* AF_RXRPC local endpoint management + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/module.h> +#include <linux/net.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <net/af_rxrpc.h> +#include "ar-internal.h" + +static LIST_HEAD(rxrpc_locals); +DEFINE_RWLOCK(rxrpc_local_lock); +static DECLARE_RWSEM(rxrpc_local_sem); +static DECLARE_WAIT_QUEUE_HEAD(rxrpc_local_wq); + +static void rxrpc_destroy_local(struct work_struct *work); + +/* + * allocate a new local + */ +static +struct rxrpc_local *rxrpc_alloc_local(struct sockaddr_rxrpc *srx) +{ + struct rxrpc_local *local; + + local = kzalloc(sizeof(struct rxrpc_local), GFP_KERNEL); + if (local) { + INIT_WORK(&local->destroyer, &rxrpc_destroy_local); + INIT_WORK(&local->acceptor, &rxrpc_accept_incoming_calls); + INIT_WORK(&local->rejecter, &rxrpc_reject_packets); + INIT_LIST_HEAD(&local->services); + INIT_LIST_HEAD(&local->link); + init_rwsem(&local->defrag_sem); + skb_queue_head_init(&local->accept_queue); + skb_queue_head_init(&local->reject_queue); + spin_lock_init(&local->lock); + rwlock_init(&local->services_lock); + atomic_set(&local->usage, 1); + local->debug_id = atomic_inc_return(&rxrpc_debug_id); + memcpy(&local->srx, srx, sizeof(*srx)); + } + + _leave(" = %p", local); + return local; +} + +/* + * create the local socket + * - must be called with rxrpc_local_sem writelocked + */ +static int rxrpc_create_local(struct rxrpc_local *local) +{ + struct sock *sock; + int ret, opt; + + _enter("%p{%d}", local, local->srx.transport_type); + + /* create a socket to represent the local endpoint */ + ret = sock_create_kern(PF_INET, local->srx.transport_type, IPPROTO_UDP, + &local->socket); + if (ret < 0) { + _leave(" = %d [socket]", ret); + return ret; + } + + /* if a local address was supplied then bind it */ + if (local->srx.transport_len > sizeof(sa_family_t)) { + _debug("bind"); + ret = kernel_bind(local->socket, + (struct sockaddr *) &local->srx.transport, + local->srx.transport_len); + if (ret < 0) { + _debug("bind failed"); + goto error; + } + } + + /* we want to receive ICMP errors */ + opt = 1; + ret = kernel_setsockopt(local->socket, SOL_IP, IP_RECVERR, + (char *) &opt, sizeof(opt)); + if (ret < 0) { + _debug("setsockopt failed"); + goto error; + } + + /* we want to set the don't fragment bit */ + opt = IP_PMTUDISC_DO; + ret = kernel_setsockopt(local->socket, SOL_IP, IP_MTU_DISCOVER, + (char *) &opt, sizeof(opt)); + if (ret < 0) { + _debug("setsockopt failed"); + goto error; + } + + write_lock_bh(&rxrpc_local_lock); + list_add(&local->link, &rxrpc_locals); + write_unlock_bh(&rxrpc_local_lock); + + /* set the socket up */ + sock = local->socket->sk; + sock->sk_user_data = local; + sock->sk_data_ready = rxrpc_data_ready; + sock->sk_error_report = rxrpc_UDP_error_report; + _leave(" = 0"); + return 0; + +error: + local->socket->ops->shutdown(local->socket, 2); + local->socket->sk->sk_user_data = NULL; + sock_release(local->socket); + local->socket = NULL; + + _leave(" = %d", ret); + return ret; +} + +/* + * create a new local endpoint using the specified UDP address + */ +struct rxrpc_local *rxrpc_lookup_local(struct sockaddr_rxrpc *srx) +{ + struct rxrpc_local *local; + int ret; + + _enter("{%d,%u,%u.%u.%u.%u+%hu}", + srx->transport_type, + srx->transport.family, + NIPQUAD(srx->transport.sin.sin_addr), + ntohs(srx->transport.sin.sin_port)); + + down_write(&rxrpc_local_sem); + + /* see if we have a suitable local local endpoint already */ + read_lock_bh(&rxrpc_local_lock); + + list_for_each_entry(local, &rxrpc_locals, link) { + _debug("CMP {%d,%u,%u.%u.%u.%u+%hu}", + local->srx.transport_type, + local->srx.transport.family, + NIPQUAD(local->srx.transport.sin.sin_addr), + ntohs(local->srx.transport.sin.sin_port)); + + if (local->srx.transport_type != srx->transport_type || + local->srx.transport.family != srx->transport.family) + continue; + + switch (srx->transport.family) { + case AF_INET: + if (local->srx.transport.sin.sin_port != + srx->transport.sin.sin_port) + continue; + if (memcmp(&local->srx.transport.sin.sin_addr, + &srx->transport.sin.sin_addr, + sizeof(struct in_addr)) != 0) + continue; + goto found_local; + + default: + BUG(); + } + } + + read_unlock_bh(&rxrpc_local_lock); + + /* we didn't find one, so we need to create one */ + local = rxrpc_alloc_local(srx); + if (!local) { + up_write(&rxrpc_local_sem); + return ERR_PTR(-ENOMEM); + } + + ret = rxrpc_create_local(local); + if (ret < 0) { + up_write(&rxrpc_local_sem); + kfree(local); + _leave(" = %d", ret); + return ERR_PTR(ret); + } + + up_write(&rxrpc_local_sem); + + _net("LOCAL new %d {%d,%u,%u.%u.%u.%u+%hu}", + local->debug_id, + local->srx.transport_type, + local->srx.transport.family, + NIPQUAD(local->srx.transport.sin.sin_addr), + ntohs(local->srx.transport.sin.sin_port)); + + _leave(" = %p [new]", local); + return local; + +found_local: + rxrpc_get_local(local); + read_unlock_bh(&rxrpc_local_lock); + up_write(&rxrpc_local_sem); + + _net("LOCAL old %d {%d,%u,%u.%u.%u.%u+%hu}", + local->debug_id, + local->srx.transport_type, + local->srx.transport.family, + NIPQUAD(local->srx.transport.sin.sin_addr), + ntohs(local->srx.transport.sin.sin_port)); + + _leave(" = %p [reuse]", local); + return local; +} + +/* + * release a local endpoint + */ +void rxrpc_put_local(struct rxrpc_local *local) +{ + _enter("%p{u=%d}", local, atomic_read(&local->usage)); + + ASSERTCMP(atomic_read(&local->usage), >, 0); + + /* to prevent a race, the decrement and the dequeue must be effectively + * atomic */ + write_lock_bh(&rxrpc_local_lock); + if (unlikely(atomic_dec_and_test(&local->usage))) { + _debug("destroy local"); + rxrpc_queue_work(&local->destroyer); + } + write_unlock_bh(&rxrpc_local_lock); + _leave(""); +} + +/* + * destroy a local endpoint + */ +static void rxrpc_destroy_local(struct work_struct *work) +{ + struct rxrpc_local *local = + container_of(work, struct rxrpc_local, destroyer); + + _enter("%p{%d}", local, atomic_read(&local->usage)); + + down_write(&rxrpc_local_sem); + + write_lock_bh(&rxrpc_local_lock); + if (atomic_read(&local->usage) > 0) { + write_unlock_bh(&rxrpc_local_lock); + up_read(&rxrpc_local_sem); + _leave(" [resurrected]"); + return; + } + + list_del(&local->link); + local->socket->sk->sk_user_data = NULL; + write_unlock_bh(&rxrpc_local_lock); + + downgrade_write(&rxrpc_local_sem); + + ASSERT(list_empty(&local->services)); + ASSERT(!work_pending(&local->acceptor)); + ASSERT(!work_pending(&local->rejecter)); + + /* finish cleaning up the local descriptor */ + rxrpc_purge_queue(&local->accept_queue); + rxrpc_purge_queue(&local->reject_queue); + local->socket->ops->shutdown(local->socket, 2); + sock_release(local->socket); + + up_read(&rxrpc_local_sem); + + _net("DESTROY LOCAL %d", local->debug_id); + kfree(local); + + if (list_empty(&rxrpc_locals)) + wake_up_all(&rxrpc_local_wq); + + _leave(""); +} + +/* + * preemptively destroy all local local endpoint rather than waiting for + * them to be destroyed + */ +void __exit rxrpc_destroy_all_locals(void) +{ + DECLARE_WAITQUEUE(myself,current); + + _enter(""); + + /* we simply have to wait for them to go away */ + if (!list_empty(&rxrpc_locals)) { + set_current_state(TASK_UNINTERRUPTIBLE); + add_wait_queue(&rxrpc_local_wq, &myself); + + while (!list_empty(&rxrpc_locals)) { + schedule(); + set_current_state(TASK_UNINTERRUPTIBLE); + } + + remove_wait_queue(&rxrpc_local_wq, &myself); + set_current_state(TASK_RUNNING); + } + + _leave(""); +} |