kernel-ark/net/bluetooth/af_bluetooth.c
Davide Libenzi f348d70a32 [PATCH] POLLRDHUP/EPOLLRDHUP handling for half-closed devices notifications
Implement the half-closed devices notifiation, by adding a new POLLRDHUP
(and its alias EPOLLRDHUP) bit to the existing poll/select sets.  Since the
existing POLLHUP handling, that does not report correctly half-closed
devices, was feared to be changed, this implementation leaves the current
POLLHUP reporting unchanged and simply add a new bit that is set in the few
places where it makes sense.  The same thing was discussed and conceptually
agreed quite some time ago:

http://lkml.org/lkml/2003/7/12/116

Since this new event bit is added to the existing Linux poll infrastruture,
even the existing poll/select system calls will be able to use it.  As far
as the existing POLLHUP handling, the patch leaves it as is.  The
pollrdhup-2.6.16.rc5-0.10.diff defines the POLLRDHUP for all the existing
archs and sets the bit in the six relevant files.  The other attached diff
is the simple change required to sys/epoll.h to add the EPOLLRDHUP
definition.

There is "a stupid program" to test POLLRDHUP delivery here:

 http://www.xmailserver.org/pollrdhup-test.c

It tests poll(2), but since the delivery is same epoll(2) will work equally.

Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:56 -08:00

341 lines
7.4 KiB
C

/*
BlueZ - Bluetooth protocol stack for Linux
Copyright (C) 2000-2001 Qualcomm Incorporated
Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2 as
published by the Free Software Foundation;
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 OF THIRD PARTY RIGHTS.
IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
SOFTWARE IS DISCLAIMED.
*/
/* Bluetooth address family and sockets. */
#include <linux/config.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <net/sock.h>
#if defined(CONFIG_KMOD)
#include <linux/kmod.h>
#endif
#include <net/bluetooth/bluetooth.h>
#ifndef CONFIG_BT_SOCK_DEBUG
#undef BT_DBG
#define BT_DBG(D...)
#endif
#define VERSION "2.8"
/* Bluetooth sockets */
#define BT_MAX_PROTO 8
static struct net_proto_family *bt_proto[BT_MAX_PROTO];
int bt_sock_register(int proto, struct net_proto_family *ops)
{
if (proto < 0 || proto >= BT_MAX_PROTO)
return -EINVAL;
if (bt_proto[proto])
return -EEXIST;
bt_proto[proto] = ops;
return 0;
}
EXPORT_SYMBOL(bt_sock_register);
int bt_sock_unregister(int proto)
{
if (proto < 0 || proto >= BT_MAX_PROTO)
return -EINVAL;
if (!bt_proto[proto])
return -ENOENT;
bt_proto[proto] = NULL;
return 0;
}
EXPORT_SYMBOL(bt_sock_unregister);
static int bt_sock_create(struct socket *sock, int proto)
{
int err = 0;
if (proto < 0 || proto >= BT_MAX_PROTO)
return -EINVAL;
#if defined(CONFIG_KMOD)
if (!bt_proto[proto]) {
request_module("bt-proto-%d", proto);
}
#endif
err = -EPROTONOSUPPORT;
if (bt_proto[proto] && try_module_get(bt_proto[proto]->owner)) {
err = bt_proto[proto]->create(sock, proto);
module_put(bt_proto[proto]->owner);
}
return err;
}
void bt_sock_link(struct bt_sock_list *l, struct sock *sk)
{
write_lock_bh(&l->lock);
sk_add_node(sk, &l->head);
write_unlock_bh(&l->lock);
}
EXPORT_SYMBOL(bt_sock_link);
void bt_sock_unlink(struct bt_sock_list *l, struct sock *sk)
{
write_lock_bh(&l->lock);
sk_del_node_init(sk);
write_unlock_bh(&l->lock);
}
EXPORT_SYMBOL(bt_sock_unlink);
void bt_accept_enqueue(struct sock *parent, struct sock *sk)
{
BT_DBG("parent %p, sk %p", parent, sk);
sock_hold(sk);
list_add_tail(&bt_sk(sk)->accept_q, &bt_sk(parent)->accept_q);
bt_sk(sk)->parent = parent;
parent->sk_ack_backlog++;
}
EXPORT_SYMBOL(bt_accept_enqueue);
void bt_accept_unlink(struct sock *sk)
{
BT_DBG("sk %p state %d", sk, sk->sk_state);
list_del_init(&bt_sk(sk)->accept_q);
bt_sk(sk)->parent->sk_ack_backlog--;
bt_sk(sk)->parent = NULL;
sock_put(sk);
}
EXPORT_SYMBOL(bt_accept_unlink);
struct sock *bt_accept_dequeue(struct sock *parent, struct socket *newsock)
{
struct list_head *p, *n;
struct sock *sk;
BT_DBG("parent %p", parent);
list_for_each_safe(p, n, &bt_sk(parent)->accept_q) {
sk = (struct sock *) list_entry(p, struct bt_sock, accept_q);
lock_sock(sk);
/* FIXME: Is this check still needed */
if (sk->sk_state == BT_CLOSED) {
release_sock(sk);
bt_accept_unlink(sk);
continue;
}
if (sk->sk_state == BT_CONNECTED || !newsock) {
bt_accept_unlink(sk);
if (newsock)
sock_graft(sk, newsock);
release_sock(sk);
return sk;
}
release_sock(sk);
}
return NULL;
}
EXPORT_SYMBOL(bt_accept_dequeue);
int bt_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t len, int flags)
{
int noblock = flags & MSG_DONTWAIT;
struct sock *sk = sock->sk;
struct sk_buff *skb;
size_t copied;
int err;
BT_DBG("sock %p sk %p len %d", sock, sk, len);
if (flags & (MSG_OOB))
return -EOPNOTSUPP;
if (!(skb = skb_recv_datagram(sk, flags, noblock, &err))) {
if (sk->sk_shutdown & RCV_SHUTDOWN)
return 0;
return err;
}
msg->msg_namelen = 0;
copied = skb->len;
if (len < copied) {
msg->msg_flags |= MSG_TRUNC;
copied = len;
}
skb->h.raw = skb->data;
err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
skb_free_datagram(sk, skb);
return err ? : copied;
}
EXPORT_SYMBOL(bt_sock_recvmsg);
static inline unsigned int bt_accept_poll(struct sock *parent)
{
struct list_head *p, *n;
struct sock *sk;
list_for_each_safe(p, n, &bt_sk(parent)->accept_q) {
sk = (struct sock *) list_entry(p, struct bt_sock, accept_q);
if (sk->sk_state == BT_CONNECTED)
return POLLIN | POLLRDNORM;
}
return 0;
}
unsigned int bt_sock_poll(struct file * file, struct socket *sock, poll_table *wait)
{
struct sock *sk = sock->sk;
unsigned int mask = 0;
BT_DBG("sock %p, sk %p", sock, sk);
poll_wait(file, sk->sk_sleep, wait);
if (sk->sk_state == BT_LISTEN)
return bt_accept_poll(sk);
if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
mask |= POLLERR;
if (sk->sk_shutdown & RCV_SHUTDOWN)
mask |= POLLRDHUP;
if (sk->sk_shutdown == SHUTDOWN_MASK)
mask |= POLLHUP;
if (!skb_queue_empty(&sk->sk_receive_queue) ||
(sk->sk_shutdown & RCV_SHUTDOWN))
mask |= POLLIN | POLLRDNORM;
if (sk->sk_state == BT_CLOSED)
mask |= POLLHUP;
if (sk->sk_state == BT_CONNECT ||
sk->sk_state == BT_CONNECT2 ||
sk->sk_state == BT_CONFIG)
return mask;
if (sock_writeable(sk))
mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
else
set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
return mask;
}
EXPORT_SYMBOL(bt_sock_poll);
int bt_sock_wait_state(struct sock *sk, int state, unsigned long timeo)
{
DECLARE_WAITQUEUE(wait, current);
int err = 0;
BT_DBG("sk %p", sk);
add_wait_queue(sk->sk_sleep, &wait);
while (sk->sk_state != state) {
set_current_state(TASK_INTERRUPTIBLE);
if (!timeo) {
err = -EAGAIN;
break;
}
if (signal_pending(current)) {
err = sock_intr_errno(timeo);
break;
}
release_sock(sk);
timeo = schedule_timeout(timeo);
lock_sock(sk);
err = sock_error(sk);
if (err)
break;
}
set_current_state(TASK_RUNNING);
remove_wait_queue(sk->sk_sleep, &wait);
return err;
}
EXPORT_SYMBOL(bt_sock_wait_state);
static struct net_proto_family bt_sock_family_ops = {
.owner = THIS_MODULE,
.family = PF_BLUETOOTH,
.create = bt_sock_create,
};
static int __init bt_init(void)
{
BT_INFO("Core ver %s", VERSION);
sock_register(&bt_sock_family_ops);
BT_INFO("HCI device and connection manager initialized");
bt_sysfs_init();
hci_sock_init();
return 0;
}
static void __exit bt_exit(void)
{
hci_sock_cleanup();
bt_sysfs_cleanup();
sock_unregister(PF_BLUETOOTH);
}
subsys_initcall(bt_init);
module_exit(bt_exit);
MODULE_AUTHOR("Maxim Krasnyansky <maxk@qualcomm.com>, Marcel Holtmann <marcel@holtmann.org>");
MODULE_DESCRIPTION("Bluetooth Core ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
MODULE_ALIAS_NETPROTO(PF_BLUETOOTH);