diff --git a/net/tipc/Makefile b/net/tipc/Makefile index 02636d0a90cf..b282f7130d2b 100644 --- a/net/tipc/Makefile +++ b/net/tipc/Makefile @@ -8,7 +8,7 @@ tipc-y += addr.o bcast.o bearer.o config.o \ core.o handler.o link.o discover.o msg.o \ name_distr.o subscr.o name_table.o net.o \ netlink.o node.o node_subscr.o port.o ref.o \ - socket.o log.o eth_media.o + socket.o log.o eth_media.o server.o tipc-$(CONFIG_TIPC_MEDIA_IB) += ib_media.o tipc-$(CONFIG_SYSCTL) += sysctl.o diff --git a/net/tipc/core.h b/net/tipc/core.h index fe7f2b7c19fe..be72f8cebc53 100644 --- a/net/tipc/core.h +++ b/net/tipc/core.h @@ -1,8 +1,8 @@ /* * net/tipc/core.h: Include file for TIPC global declarations * - * Copyright (c) 2005-2006, Ericsson AB - * Copyright (c) 2005-2007, 2010-2011, Wind River Systems + * Copyright (c) 2005-2006, 2013 Ericsson AB + * Copyright (c) 2005-2007, 2010-2013, Wind River Systems * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -97,6 +97,10 @@ extern int tipc_netlink_start(void); extern void tipc_netlink_stop(void); extern int tipc_socket_init(void); extern void tipc_socket_stop(void); +extern int tipc_sock_create_local(int type, struct socket **res); +extern void tipc_sock_release_local(struct socket *sock); +extern int tipc_sock_accept_local(struct socket *sock, + struct socket **newsock, int flags); #ifdef CONFIG_SYSCTL extern int tipc_register_sysctl(void); diff --git a/net/tipc/server.c b/net/tipc/server.c new file mode 100644 index 000000000000..19da5abe0fa6 --- /dev/null +++ b/net/tipc/server.c @@ -0,0 +1,596 @@ +/* + * net/tipc/server.c: TIPC server infrastructure + * + * Copyright (c) 2012-2013, Wind River Systems + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * 3. Neither the names of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * Alternatively, this software may be distributed under the terms of the + * GNU General Public License ("GPL") version 2 as published by the Free + * Software Foundation. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include "server.h" +#include "core.h" +#include + +/* Number of messages to send before rescheduling */ +#define MAX_SEND_MSG_COUNT 25 +#define MAX_RECV_MSG_COUNT 25 +#define CF_CONNECTED 1 + +#define sock2con(x) ((struct tipc_conn *)(x)->sk_user_data) + +/** + * struct tipc_conn - TIPC connection structure + * @kref: reference counter to connection object + * @conid: connection identifier + * @sock: socket handler associated with connection + * @flags: indicates connection state + * @server: pointer to connected server + * @rwork: receive work item + * @usr_data: user-specified field + * @rx_action: what to do when connection socket is active + * @outqueue: pointer to first outbound message in queue + * @outqueue_lock: controll access to the outqueue + * @outqueue: list of connection objects for its server + * @swork: send work item + */ +struct tipc_conn { + struct kref kref; + int conid; + struct socket *sock; + unsigned long flags; + struct tipc_server *server; + struct work_struct rwork; + int (*rx_action) (struct tipc_conn *con); + void *usr_data; + struct list_head outqueue; + spinlock_t outqueue_lock; + struct work_struct swork; +}; + +/* An entry waiting to be sent */ +struct outqueue_entry { + struct list_head list; + struct kvec iov; + struct sockaddr_tipc dest; +}; + +static void tipc_recv_work(struct work_struct *work); +static void tipc_send_work(struct work_struct *work); +static void tipc_clean_outqueues(struct tipc_conn *con); + +static void tipc_conn_kref_release(struct kref *kref) +{ + struct tipc_conn *con = container_of(kref, struct tipc_conn, kref); + struct tipc_server *s = con->server; + + if (con->sock) { + tipc_sock_release_local(con->sock); + con->sock = NULL; + } + + tipc_clean_outqueues(con); + + if (con->conid) + s->tipc_conn_shutdown(con->conid, con->usr_data); + + kfree(con); +} + +static void conn_put(struct tipc_conn *con) +{ + kref_put(&con->kref, tipc_conn_kref_release); +} + +static void conn_get(struct tipc_conn *con) +{ + kref_get(&con->kref); +} + +static struct tipc_conn *tipc_conn_lookup(struct tipc_server *s, int conid) +{ + struct tipc_conn *con; + + spin_lock_bh(&s->idr_lock); + con = idr_find(&s->conn_idr, conid); + if (con) + conn_get(con); + spin_unlock_bh(&s->idr_lock); + return con; +} + +static void sock_data_ready(struct sock *sk, int unused) +{ + struct tipc_conn *con; + + read_lock(&sk->sk_callback_lock); + con = sock2con(sk); + if (con && test_bit(CF_CONNECTED, &con->flags)) { + conn_get(con); + if (!queue_work(con->server->rcv_wq, &con->rwork)) + conn_put(con); + } + read_unlock(&sk->sk_callback_lock); +} + +static void sock_write_space(struct sock *sk) +{ + struct tipc_conn *con; + + read_lock(&sk->sk_callback_lock); + con = sock2con(sk); + if (con && test_bit(CF_CONNECTED, &con->flags)) { + conn_get(con); + if (!queue_work(con->server->send_wq, &con->swork)) + conn_put(con); + } + read_unlock(&sk->sk_callback_lock); +} + +static void tipc_register_callbacks(struct socket *sock, struct tipc_conn *con) +{ + struct sock *sk = sock->sk; + + write_lock_bh(&sk->sk_callback_lock); + + sk->sk_data_ready = sock_data_ready; + sk->sk_write_space = sock_write_space; + sk->sk_user_data = con; + + con->sock = sock; + + write_unlock_bh(&sk->sk_callback_lock); +} + +static void tipc_unregister_callbacks(struct tipc_conn *con) +{ + struct sock *sk = con->sock->sk; + + write_lock_bh(&sk->sk_callback_lock); + sk->sk_user_data = NULL; + write_unlock_bh(&sk->sk_callback_lock); +} + +static void tipc_close_conn(struct tipc_conn *con) +{ + struct tipc_server *s = con->server; + + if (test_and_clear_bit(CF_CONNECTED, &con->flags)) { + spin_lock_bh(&s->idr_lock); + idr_remove(&s->conn_idr, con->conid); + s->idr_in_use--; + spin_unlock_bh(&s->idr_lock); + + tipc_unregister_callbacks(con); + + /* We shouldn't flush pending works as we may be in the + * thread. In fact the races with pending rx/tx work structs + * are harmless for us here as we have already deleted this + * connection from server connection list and set + * sk->sk_user_data to 0 before releasing connection object. + */ + kernel_sock_shutdown(con->sock, SHUT_RDWR); + + conn_put(con); + } +} + +static struct tipc_conn *tipc_alloc_conn(struct tipc_server *s) +{ + struct tipc_conn *con; + int ret; + + con = kzalloc(sizeof(struct tipc_conn), GFP_ATOMIC); + if (!con) + return ERR_PTR(-ENOMEM); + + kref_init(&con->kref); + INIT_LIST_HEAD(&con->outqueue); + spin_lock_init(&con->outqueue_lock); + INIT_WORK(&con->swork, tipc_send_work); + INIT_WORK(&con->rwork, tipc_recv_work); + + spin_lock_bh(&s->idr_lock); + ret = idr_alloc(&s->conn_idr, con, 0, 0, GFP_ATOMIC); + if (ret < 0) { + kfree(con); + spin_unlock_bh(&s->idr_lock); + return ERR_PTR(-ENOMEM); + } + con->conid = ret; + s->idr_in_use++; + spin_unlock_bh(&s->idr_lock); + + set_bit(CF_CONNECTED, &con->flags); + con->server = s; + + return con; +} + +static int tipc_receive_from_sock(struct tipc_conn *con) +{ + struct msghdr msg = {}; + struct tipc_server *s = con->server; + struct sockaddr_tipc addr; + struct kvec iov; + void *buf; + int ret; + + buf = kmem_cache_alloc(s->rcvbuf_cache, GFP_ATOMIC); + if (!buf) { + ret = -ENOMEM; + goto out_close; + } + + iov.iov_base = buf; + iov.iov_len = s->max_rcvbuf_size; + msg.msg_name = &addr; + ret = kernel_recvmsg(con->sock, &msg, &iov, 1, iov.iov_len, + MSG_DONTWAIT); + if (ret <= 0) { + kmem_cache_free(s->rcvbuf_cache, buf); + goto out_close; + } + + s->tipc_conn_recvmsg(con->conid, &addr, con->usr_data, buf, ret); + + kmem_cache_free(s->rcvbuf_cache, buf); + + return 0; + +out_close: + if (ret != -EWOULDBLOCK) + tipc_close_conn(con); + else if (ret == 0) + /* Don't return success if we really got EOF */ + ret = -EAGAIN; + + return ret; +} + +static int tipc_accept_from_sock(struct tipc_conn *con) +{ + struct tipc_server *s = con->server; + struct socket *sock = con->sock; + struct socket *newsock; + struct tipc_conn *newcon; + int ret; + + ret = tipc_sock_accept_local(sock, &newsock, O_NONBLOCK); + if (ret < 0) + return ret; + + newcon = tipc_alloc_conn(con->server); + if (IS_ERR(newcon)) { + ret = PTR_ERR(newcon); + sock_release(newsock); + return ret; + } + + newcon->rx_action = tipc_receive_from_sock; + tipc_register_callbacks(newsock, newcon); + + /* Notify that new connection is incoming */ + newcon->usr_data = s->tipc_conn_new(newcon->conid); + + /* Wake up receive process in case of 'SYN+' message */ + newsock->sk->sk_data_ready(newsock->sk, 0); + return ret; +} + +static struct socket *tipc_create_listen_sock(struct tipc_conn *con) +{ + struct tipc_server *s = con->server; + struct socket *sock = NULL; + int ret; + + ret = tipc_sock_create_local(s->type, &sock); + if (ret < 0) + return NULL; + ret = kernel_setsockopt(sock, SOL_TIPC, TIPC_IMPORTANCE, + (char *)&s->imp, sizeof(s->imp)); + if (ret < 0) + goto create_err; + ret = kernel_bind(sock, (struct sockaddr *)s->saddr, sizeof(*s->saddr)); + if (ret < 0) + goto create_err; + + switch (s->type) { + case SOCK_STREAM: + case SOCK_SEQPACKET: + con->rx_action = tipc_accept_from_sock; + + ret = kernel_listen(sock, 0); + if (ret < 0) + goto create_err; + break; + case SOCK_DGRAM: + case SOCK_RDM: + con->rx_action = tipc_receive_from_sock; + break; + default: + pr_err("Unknown socket type %d\n", s->type); + goto create_err; + } + return sock; + +create_err: + sock_release(sock); + con->sock = NULL; + return NULL; +} + +static int tipc_open_listening_sock(struct tipc_server *s) +{ + struct socket *sock; + struct tipc_conn *con; + + con = tipc_alloc_conn(s); + if (IS_ERR(con)) + return PTR_ERR(con); + + sock = tipc_create_listen_sock(con); + if (!sock) + return -EINVAL; + + tipc_register_callbacks(sock, con); + return 0; +} + +static struct outqueue_entry *tipc_alloc_entry(void *data, int len) +{ + struct outqueue_entry *entry; + void *buf; + + entry = kmalloc(sizeof(struct outqueue_entry), GFP_ATOMIC); + if (!entry) + return NULL; + + buf = kmalloc(len, GFP_ATOMIC); + if (!buf) { + kfree(entry); + return NULL; + } + + memcpy(buf, data, len); + entry->iov.iov_base = buf; + entry->iov.iov_len = len; + + return entry; +} + +static void tipc_free_entry(struct outqueue_entry *e) +{ + kfree(e->iov.iov_base); + kfree(e); +} + +static void tipc_clean_outqueues(struct tipc_conn *con) +{ + struct outqueue_entry *e, *safe; + + spin_lock_bh(&con->outqueue_lock); + list_for_each_entry_safe(e, safe, &con->outqueue, list) { + list_del(&e->list); + tipc_free_entry(e); + } + spin_unlock_bh(&con->outqueue_lock); +} + +int tipc_conn_sendmsg(struct tipc_server *s, int conid, + struct sockaddr_tipc *addr, void *data, size_t len) +{ + struct outqueue_entry *e; + struct tipc_conn *con; + + con = tipc_conn_lookup(s, conid); + if (!con) + return -EINVAL; + + e = tipc_alloc_entry(data, len); + if (!e) { + conn_put(con); + return -ENOMEM; + } + + if (addr) + memcpy(&e->dest, addr, sizeof(struct sockaddr_tipc)); + + spin_lock_bh(&con->outqueue_lock); + list_add_tail(&e->list, &con->outqueue); + spin_unlock_bh(&con->outqueue_lock); + + if (test_bit(CF_CONNECTED, &con->flags)) + if (!queue_work(s->send_wq, &con->swork)) + conn_put(con); + + return 0; +} + +void tipc_conn_terminate(struct tipc_server *s, int conid) +{ + struct tipc_conn *con; + + con = tipc_conn_lookup(s, conid); + if (con) { + tipc_close_conn(con); + conn_put(con); + } +} + +static void tipc_send_to_sock(struct tipc_conn *con) +{ + int count = 0; + struct tipc_server *s = con->server; + struct outqueue_entry *e; + struct msghdr msg; + int ret; + + spin_lock_bh(&con->outqueue_lock); + while (1) { + e = list_entry(con->outqueue.next, struct outqueue_entry, + list); + if ((struct list_head *) e == &con->outqueue) + break; + spin_unlock_bh(&con->outqueue_lock); + + memset(&msg, 0, sizeof(msg)); + msg.msg_flags = MSG_DONTWAIT; + + if (s->type == SOCK_DGRAM || s->type == SOCK_RDM) { + msg.msg_name = &e->dest; + msg.msg_namelen = sizeof(struct sockaddr_tipc); + } + ret = kernel_sendmsg(con->sock, &msg, &e->iov, 1, + e->iov.iov_len); + if (ret == -EWOULDBLOCK || ret == 0) { + cond_resched(); + goto out; + } else if (ret < 0) { + goto send_err; + } + + /* Don't starve users filling buffers */ + if (++count >= MAX_SEND_MSG_COUNT) { + cond_resched(); + count = 0; + } + + spin_lock_bh(&con->outqueue_lock); + list_del(&e->list); + tipc_free_entry(e); + } + spin_unlock_bh(&con->outqueue_lock); +out: + return; + +send_err: + tipc_close_conn(con); +} + +static void tipc_recv_work(struct work_struct *work) +{ + struct tipc_conn *con = container_of(work, struct tipc_conn, rwork); + int count = 0; + + while (test_bit(CF_CONNECTED, &con->flags)) { + if (con->rx_action(con)) + break; + + /* Don't flood Rx machine */ + if (++count >= MAX_RECV_MSG_COUNT) { + cond_resched(); + count = 0; + } + } + conn_put(con); +} + +static void tipc_send_work(struct work_struct *work) +{ + struct tipc_conn *con = container_of(work, struct tipc_conn, swork); + + if (test_bit(CF_CONNECTED, &con->flags)) + tipc_send_to_sock(con); + + conn_put(con); +} + +static void tipc_work_stop(struct tipc_server *s) +{ + destroy_workqueue(s->rcv_wq); + destroy_workqueue(s->send_wq); +} + +static int tipc_work_start(struct tipc_server *s) +{ + s->rcv_wq = alloc_workqueue("tipc_rcv", WQ_UNBOUND, 1); + if (!s->rcv_wq) { + pr_err("can't start tipc receive workqueue\n"); + return -ENOMEM; + } + + s->send_wq = alloc_workqueue("tipc_send", WQ_UNBOUND, 1); + if (!s->send_wq) { + pr_err("can't start tipc send workqueue\n"); + destroy_workqueue(s->rcv_wq); + return -ENOMEM; + } + + return 0; +} + +int tipc_server_start(struct tipc_server *s) +{ + int ret; + + spin_lock_init(&s->idr_lock); + idr_init(&s->conn_idr); + s->idr_in_use = 0; + + s->rcvbuf_cache = kmem_cache_create(s->name, s->max_rcvbuf_size, + 0, SLAB_HWCACHE_ALIGN, NULL); + if (!s->rcvbuf_cache) + return -ENOMEM; + + ret = tipc_work_start(s); + if (ret < 0) { + kmem_cache_destroy(s->rcvbuf_cache); + return ret; + } + s->enabled = 1; + + return tipc_open_listening_sock(s); +} + +void tipc_server_stop(struct tipc_server *s) +{ + struct tipc_conn *con; + int total = 0; + int id; + + if (!s->enabled) + return; + + s->enabled = 0; + spin_lock_bh(&s->idr_lock); + for (id = 0; total < s->idr_in_use; id++) { + con = idr_find(&s->conn_idr, id); + if (con) { + total++; + spin_unlock_bh(&s->idr_lock); + tipc_close_conn(con); + spin_lock_bh(&s->idr_lock); + } + } + spin_unlock_bh(&s->idr_lock); + + tipc_work_stop(s); + kmem_cache_destroy(s->rcvbuf_cache); + idr_destroy(&s->conn_idr); +} diff --git a/net/tipc/server.h b/net/tipc/server.h new file mode 100644 index 000000000000..98b23f20bc0f --- /dev/null +++ b/net/tipc/server.h @@ -0,0 +1,94 @@ +/* + * net/tipc/server.h: Include file for TIPC server code + * + * Copyright (c) 2012-2013, Wind River Systems + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * 3. Neither the names of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * Alternatively, this software may be distributed under the terms of the + * GNU General Public License ("GPL") version 2 as published by the Free + * Software Foundation. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef _TIPC_SERVER_H +#define _TIPC_SERVER_H + +#include "core.h" + +#define TIPC_SERVER_NAME_LEN 32 + +/** + * struct tipc_server - TIPC server structure + * @conn_idr: identifier set of connection + * @idr_lock: protect the connection identifier set + * @idr_in_use: amount of allocated identifier entry + * @rcvbuf_cache: memory cache of server receive buffer + * @rcv_wq: receive workqueue + * @send_wq: send workqueue + * @max_rcvbuf_size: maximum permitted receive message length + * @tipc_conn_new: callback will be called when new connection is incoming + * @tipc_conn_shutdown: callback will be called when connection is shut down + * @tipc_conn_recvmsg: callback will be called when message arrives + * @saddr: TIPC server address + * @name: server name + * @imp: message importance + * @type: socket type + * @enabled: identify whether server is launched or not + */ +struct tipc_server { + struct idr conn_idr; + spinlock_t idr_lock; + int idr_in_use; + struct kmem_cache *rcvbuf_cache; + struct workqueue_struct *rcv_wq; + struct workqueue_struct *send_wq; + int max_rcvbuf_size; + void *(*tipc_conn_new) (int conid); + void (*tipc_conn_shutdown) (int conid, void *usr_data); + void (*tipc_conn_recvmsg) (int conid, struct sockaddr_tipc *addr, + void *usr_data, void *buf, size_t len); + struct sockaddr_tipc *saddr; + const char name[TIPC_SERVER_NAME_LEN]; + int imp; + int type; + int enabled; +}; + +int tipc_conn_sendmsg(struct tipc_server *s, int conid, + struct sockaddr_tipc *addr, void *data, size_t len); + +/** + * tipc_conn_terminate - terminate connection with server + * + * Note: Must call it in process context since it might sleep + */ +void tipc_conn_terminate(struct tipc_server *s, int conid); + +int tipc_server_start(struct tipc_server *s); + +void tipc_server_stop(struct tipc_server *s); + +#endif diff --git a/net/tipc/socket.c b/net/tipc/socket.c index d5fa708f037d..bd8e2cdeceef 100644 --- a/net/tipc/socket.c +++ b/net/tipc/socket.c @@ -2,7 +2,7 @@ * net/tipc/socket.c: TIPC socket API * * Copyright (c) 2001-2007, 2012 Ericsson AB - * Copyright (c) 2004-2008, 2010-2012, Wind River Systems + * Copyright (c) 2004-2008, 2010-2013, Wind River Systems * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -63,12 +63,15 @@ static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf); static void wakeupdispatch(struct tipc_port *tport); static void tipc_data_ready(struct sock *sk, int len); static void tipc_write_space(struct sock *sk); +static int release(struct socket *sock); +static int accept(struct socket *sock, struct socket *new_sock, int flags); static const struct proto_ops packet_ops; static const struct proto_ops stream_ops; static const struct proto_ops msg_ops; static struct proto tipc_proto; +static struct proto tipc_proto_kern; static int sockets_enabled; @@ -141,7 +144,7 @@ static void reject_rx_queue(struct sock *sk) } /** - * tipc_create - create a TIPC socket + * tipc_sk_create - create a TIPC socket * @net: network namespace (must be default network) * @sock: pre-allocated socket structure * @protocol: protocol indicator (must be 0) @@ -152,8 +155,8 @@ static void reject_rx_queue(struct sock *sk) * * Returns 0 on success, errno otherwise */ -static int tipc_create(struct net *net, struct socket *sock, int protocol, - int kern) +static int tipc_sk_create(struct net *net, struct socket *sock, int protocol, + int kern) { const struct proto_ops *ops; socket_state state; @@ -183,7 +186,11 @@ static int tipc_create(struct net *net, struct socket *sock, int protocol, } /* Allocate socket's protocol area */ - sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto); + if (!kern) + sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto); + else + sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto_kern); + if (sk == NULL) return -ENOMEM; @@ -218,6 +225,78 @@ static int tipc_create(struct net *net, struct socket *sock, int protocol, return 0; } +/** + * tipc_sock_create_local - create TIPC socket from inside TIPC module + * @type: socket type - SOCK_RDM or SOCK_SEQPACKET + * + * We cannot use sock_creat_kern here because it bumps module user count. + * Since socket owner and creator is the same module we must make sure + * that module count remains zero for module local sockets, otherwise + * we cannot do rmmod. + * + * Returns 0 on success, errno otherwise + */ +int tipc_sock_create_local(int type, struct socket **res) +{ + int rc; + struct sock *sk; + + rc = sock_create_lite(AF_TIPC, type, 0, res); + if (rc < 0) { + pr_err("Failed to create kernel socket\n"); + return rc; + } + tipc_sk_create(&init_net, *res, 0, 1); + + sk = (*res)->sk; + + return 0; +} + +/** + * tipc_sock_release_local - release socket created by tipc_sock_create_local + * @sock: the socket to be released. + * + * Module reference count is not incremented when such sockets are created, + * so we must keep it from being decremented when they are released. + */ +void tipc_sock_release_local(struct socket *sock) +{ + release(sock); + sock->ops = NULL; + sock_release(sock); +} + +/** + * tipc_sock_accept_local - accept a connection on a socket created + * with tipc_sock_create_local. Use this function to avoid that + * module reference count is inadvertently incremented. + * + * @sock: the accepting socket + * @newsock: reference to the new socket to be created + * @flags: socket flags + */ + +int tipc_sock_accept_local(struct socket *sock, struct socket **newsock, + int flags) +{ + struct sock *sk = sock->sk; + int ret; + + ret = sock_create_lite(sk->sk_family, sk->sk_type, + sk->sk_protocol, newsock); + if (ret < 0) + return ret; + + ret = accept(sock, *newsock, flags); + if (ret < 0) { + sock_release(*newsock); + return ret; + } + (*newsock)->ops = sock->ops; + return ret; +} + /** * release - destroy a TIPC socket * @sock: socket to destroy @@ -1529,7 +1608,7 @@ static int accept(struct socket *sock, struct socket *new_sock, int flags) buf = skb_peek(&sk->sk_receive_queue); - res = tipc_create(sock_net(sock->sk), new_sock, 0, 0); + res = tipc_sk_create(sock_net(sock->sk), new_sock, 0, 1); if (res) goto exit; @@ -1839,7 +1918,7 @@ static const struct proto_ops stream_ops = { static const struct net_proto_family tipc_family_ops = { .owner = THIS_MODULE, .family = AF_TIPC, - .create = tipc_create + .create = tipc_sk_create }; static struct proto tipc_proto = { @@ -1849,6 +1928,12 @@ static struct proto tipc_proto = { .sysctl_rmem = sysctl_tipc_rmem }; +static struct proto tipc_proto_kern = { + .name = "TIPC", + .obj_size = sizeof(struct tipc_sock), + .sysctl_rmem = sysctl_tipc_rmem +}; + /** * tipc_socket_init - initialize TIPC socket interface *