static void svc_disconnect(struct atm_vcc *vcc)
{
DEFINE_WAIT(wait);
struct sk_buff *skb;
struct sock *sk = sk_atm(vcc);
pr_debug("%p\n", vcc);
if (test_bit(ATM_VF_REGIS, &vcc->flags)) {
prepare_to_wait(sk_sleep(sk), &wait, TASK_UNINTERRUPTIBLE);
sigd_enq(vcc, as_close, NULL, NULL, NULL);
while (!test_bit(ATM_VF_RELEASED, &vcc->flags) && sigd) {
schedule();
prepare_to_wait(sk_sleep(sk), &wait,
TASK_UNINTERRUPTIBLE);
}
finish_wait(sk_sleep(sk), &wait);
}
/* beware - socket is still in use by atmsigd until the last
as_indicate has been answered */
while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
atm_return(vcc, skb->truesize);
pr_debug("LISTEN REL\n");
sigd_enq2(NULL, as_reject, vcc, NULL, NULL, &vcc->qos, 0);
dev_kfree_skb(skb);
}
clear_bit(ATM_VF_REGIS, &vcc->flags);
/* ... may retry later */
}
/**
* sk_stream_wait_connect - Wait for a socket to get into the connected state
* @sk: sock to wait on
* @timeo_p: for how long to wait
*
* Must be called with the socket locked.
*/
int sk_stream_wait_connect(struct sock *sk, long *timeo_p)
{
struct task_struct *tsk = current;
DEFINE_WAIT(wait);
int done;
do {
int err = sock_error(sk);
if (err)
return err;
if ((1 << sk->sk_state) & ~(TCPF_SYN_SENT | TCPF_SYN_RECV))
return -EPIPE;
if (!*timeo_p)
return -EAGAIN;
if (signal_pending(tsk))
return sock_intr_errno(*timeo_p);
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
sk->sk_write_pending++;
done = sk_wait_event(sk, timeo_p,
!sk->sk_err &&
!((1 << sk->sk_state) &
~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)));
finish_wait(sk_sleep(sk), &wait);
sk->sk_write_pending--;
} while (!done);
return 0;
}
static int svc_addparty(struct socket *sock, struct sockaddr *sockaddr,
int sockaddr_len, int flags)
{
DEFINE_WAIT(wait);
struct sock *sk = sock->sk;
struct atm_vcc *vcc = ATM_SD(sock);
int error;
lock_sock(sk);
set_bit(ATM_VF_WAITING, &vcc->flags);
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
sigd_enq(vcc, as_addparty, NULL, NULL,
(struct sockaddr_atmsvc *) sockaddr);
if (flags & O_NONBLOCK) {
finish_wait(sk_sleep(sk), &wait);
error = -EINPROGRESS;
goto out;
}
pr_debug("added wait queue\n");
while (test_bit(ATM_VF_WAITING, &vcc->flags) && sigd) {
schedule();
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
}
finish_wait(sk_sleep(sk), &wait);
error = xchg(&sk->sk_err_soft, 0);
out:
release_sock(sk);
return error;
}
/* wait for sndbuf data being transmitted */
static void smc_close_stream_wait(struct smc_sock *smc, long timeout)
{
DEFINE_WAIT_FUNC(wait, woken_wake_function);
struct sock *sk = &smc->sk;
if (!timeout)
return;
if (!smc_tx_prepared_sends(&smc->conn))
return;
smc->wait_close_tx_prepared = 1;
add_wait_queue(sk_sleep(sk), &wait);
while (!signal_pending(current) && timeout) {
int rc;
rc = sk_wait_event(sk, &timeout,
!smc_tx_prepared_sends(&smc->conn) ||
(sk->sk_err == ECONNABORTED) ||
(sk->sk_err == ECONNRESET),
&wait);
if (rc)
break;
}
remove_wait_queue(sk_sleep(sk), &wait);
smc->wait_close_tx_prepared = 0;
}
static int svc_dropparty(struct socket *sock, int ep_ref)
{
DEFINE_WAIT(wait);
struct sock *sk = sock->sk;
struct atm_vcc *vcc = ATM_SD(sock);
int error;
lock_sock(sk);
set_bit(ATM_VF_WAITING, &vcc->flags);
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
sigd_enq2(vcc, as_dropparty, NULL, NULL, NULL, NULL, ep_ref);
while (test_bit(ATM_VF_WAITING, &vcc->flags) && sigd) {
schedule();
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
}
finish_wait(sk_sleep(sk), &wait);
if (!sigd) {
error = -EUNATCH;
goto out;
}
error = xchg(&sk->sk_err_soft, 0);
out:
release_sock(sk);
return error;
}
static int pep_wait_connreq(struct sock *sk, int noblock)
{
struct task_struct *tsk = current;
struct pep_sock *pn = pep_sk(sk);
long timeo = sock_rcvtimeo(sk, noblock);
for (;;) {
DEFINE_WAIT(wait);
if (sk->sk_state != TCP_LISTEN)
return -EINVAL;
if (!hlist_empty(&pn->ackq))
break;
if (!timeo)
return -EWOULDBLOCK;
if (signal_pending(tsk))
return sock_intr_errno(timeo);
prepare_to_wait_exclusive(sk_sleep(sk), &wait,
TASK_INTERRUPTIBLE);
release_sock(sk);
timeo = schedule_timeout(timeo);
lock_sock(sk);
finish_wait(sk_sleep(sk), &wait);
}
return 0;
}
static void wakeupdispatch(struct tipc_port *tport)
{
struct sock *sk = (struct sock *)tport->usr_handle;
if (waitqueue_active(sk_sleep(sk)))
wake_up_interruptible(sk_sleep(sk));
}
int sk_stream_wait_memory(struct sock *sk, long *timeo_p)
{
int err = 0;
long vm_wait = 0;
long current_timeo = *timeo_p;
DEFINE_WAIT(wait);
if (sk_stream_memory_free(sk))
current_timeo = vm_wait = (net_random() % (HZ / 5)) + 2;
while (1) {
set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
goto do_error;
if (!*timeo_p)
goto do_nonblock;
if (signal_pending(current))
goto do_interrupted;
clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
if (sk_stream_memory_free(sk) && !vm_wait)
break;
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
sk->sk_write_pending++;
sk_wait_event(sk, ¤t_timeo, sk->sk_err ||
(sk->sk_shutdown & SEND_SHUTDOWN) ||
(sk_stream_memory_free(sk) &&
!vm_wait));
sk->sk_write_pending--;
if (vm_wait) {
vm_wait -= current_timeo;
current_timeo = *timeo_p;
if (current_timeo != MAX_SCHEDULE_TIMEOUT &&
(current_timeo -= vm_wait) < 0)
current_timeo = 0;
vm_wait = 0;
}
*timeo_p = current_timeo;
}
out:
finish_wait(sk_sleep(sk), &wait);
return err;
do_error:
err = -EPIPE;
goto out;
do_nonblock:
err = -EAGAIN;
goto out;
do_interrupted:
err = sock_intr_errno(*timeo_p);
goto out;
}
static int l2cap_sock_accept(struct socket *sock, struct socket *newsock,
int flags)
{
DEFINE_WAIT_FUNC(wait, woken_wake_function);
struct sock *sk = sock->sk, *nsk;
long timeo;
int err = 0;
lock_sock_nested(sk, L2CAP_NESTING_PARENT);
timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
BT_DBG("sk %p timeo %ld", sk, timeo);
/* Wait for an incoming connection. (wake-one). */
add_wait_queue_exclusive(sk_sleep(sk), &wait);
while (1) {
if (sk->sk_state != BT_LISTEN) {
err = -EBADFD;
break;
}
nsk = bt_accept_dequeue(sk, newsock);
if (nsk)
break;
if (!timeo) {
err = -EAGAIN;
break;
}
if (signal_pending(current)) {
err = sock_intr_errno(timeo);
break;
}
release_sock(sk);
timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
lock_sock_nested(sk, L2CAP_NESTING_PARENT);
}
remove_wait_queue(sk_sleep(sk), &wait);
if (err)
goto done;
newsock->state = SS_CONNECTED;
BT_DBG("new socket %p", nsk);
done:
release_sock(sk);
return err;
}
static int l2cap_sock_accept(struct socket *sock, struct socket *newsock, int flags)
{
DECLARE_WAITQUEUE(wait, current);
struct sock *sk = sock->sk, *nsk;
long timeo;
int err = 0;
lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
if (sk->sk_state != BT_LISTEN) {
err = -EBADFD;
goto done;
}
timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
BT_DBG("sk %p timeo %ld", sk, timeo);
/* Wait for an incoming connection. (wake-one). */
add_wait_queue_exclusive(sk_sleep(sk), &wait);
while (!(nsk = bt_accept_dequeue(sk, newsock))) {
set_current_state(TASK_INTERRUPTIBLE);
if (!timeo) {
err = -EAGAIN;
break;
}
release_sock(sk);
timeo = schedule_timeout(timeo);
lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
if (sk->sk_state != BT_LISTEN) {
err = -EBADFD;
break;
}
if (signal_pending(current)) {
err = sock_intr_errno(timeo);
break;
}
}
set_current_state(TASK_RUNNING);
remove_wait_queue(sk_sleep(sk), &wait);
if (err)
goto done;
newsock->state = SS_CONNECTED;
BT_DBG("new socket %p", nsk);
done:
release_sock(sk);
return err;
}
static int svc_bind(struct socket *sock, struct sockaddr *sockaddr,
int sockaddr_len)
{
DEFINE_WAIT(wait);
struct sock *sk = sock->sk;
struct sockaddr_atmsvc *addr;
struct atm_vcc *vcc;
int error;
if (sockaddr_len != sizeof(struct sockaddr_atmsvc))
return -EINVAL;
lock_sock(sk);
if (sock->state == SS_CONNECTED) {
error = -EISCONN;
goto out;
}
if (sock->state != SS_UNCONNECTED) {
error = -EINVAL;
goto out;
}
vcc = ATM_SD(sock);
addr = (struct sockaddr_atmsvc *) sockaddr;
if (addr->sas_family != AF_ATMSVC) {
error = -EAFNOSUPPORT;
goto out;
}
clear_bit(ATM_VF_BOUND, &vcc->flags);
/* failing rebind will kill old binding */
/* @@@ check memory (de)allocation on rebind */
if (!test_bit(ATM_VF_HASQOS, &vcc->flags)) {
error = -EBADFD;
goto out;
}
vcc->local = *addr;
set_bit(ATM_VF_WAITING, &vcc->flags);
sigd_enq(vcc, as_bind, NULL, NULL, &vcc->local);
for (;;) {
prepare_to_wait(sk_sleep(sk), &wait, TASK_UNINTERRUPTIBLE);
if (!test_bit(ATM_VF_WAITING, &vcc->flags) || !sigd)
break;
schedule();
}
finish_wait(sk_sleep(sk), &wait);
clear_bit(ATM_VF_REGIS, &vcc->flags); /* doesn't count */
if (!sigd) {
error = -EUNATCH;
goto out;
}
if (!sk->sk_err)
set_bit(ATM_VF_BOUND, &vcc->flags);
error = -sk->sk_err;
out:
release_sock(sk);
return error;
}
static int shutdown(struct socket *sock, int how)
{
struct sock *sk = sock->sk;
struct tipc_port *tport = tipc_sk_port(sk);
struct sk_buff *buf;
int res;
if (how != SHUT_RDWR)
return -EINVAL;
lock_sock(sk);
switch (sock->state) {
case SS_CONNECTING:
case SS_CONNECTED:
/* Disconnect and send a 'FIN+' or 'FIN-' message to peer */
restart:
buf = __skb_dequeue(&sk->sk_receive_queue);
if (buf) {
atomic_dec(&tipc_queue_size);
if (TIPC_SKB_CB(buf)->handle != 0) {
kfree_skb(buf);
goto restart;
}
tipc_disconnect(tport->ref);
tipc_reject_msg(buf, TIPC_CONN_SHUTDOWN);
} else {
tipc_shutdown(tport->ref);
}
sock->state = SS_DISCONNECTING;
/* fall through */
case SS_DISCONNECTING:
/* Discard any unreceived messages; wake up sleeping tasks */
discard_rx_queue(sk);
if (waitqueue_active(sk_sleep(sk)))
wake_up_interruptible(sk_sleep(sk));
res = 0;
break;
default:
res = -ENOTCONN;
}
release_sock(sk);
return res;
}
/*
* Wait for a packet..
*/
static int wait_for_packet(struct sock *sk, int *err, long *timeo_p)
{
int error;
DEFINE_WAIT_FUNC(wait, receiver_wake_function);
/*
前面的操作都是初始化wait，为将socket加入wait队列作准备，这部分代码牵涉到进程调度。关于进程调度，我 只是知道一些皮毛，留在以后学习。这里只需要将其看作是一些加入wait队列的准备工作即可，并不影响理解代码 。
*/
prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
/* Socket errors? */
error = sock_error(sk);
if (error)
goto out_err;
/* 一个完备检测。在决定wait和调用wait之间，有数据包到了，那么就不需要wait，所以这里再次检查socket 的队列是否为空 */
if (!skb_queue_empty(&sk->sk_receive_queue))
goto out;
/* Socket shut down? */
/* 完备检测。也许socket无数据包读取，因为socket已经被另外的线程关闭了。这样可以保证关闭socket的时 候，不会导致其他的socket的读写操作被阻塞。*/
if (sk->sk_shutdown & RCV_SHUTDOWN)
goto out_noerr;
/* Sequenced packets can come disconnected.
* If so we report the problem
*//* 对于面向连接的socket进行检查。如果是面向连接的socket，如果不是已经建立连接或者正在监听状态的so cket是不可能有数据包的。不然即出错*/
error = -ENOTCONN;
if (connection_based(sk) &&
!(sk->sk_state == TCP_ESTABLISHED || sk->sk_state == TCP_LISTEN))
goto out_err;
/* handle signals */
if (signal_pending(current))/* 检查是否有pending的signal，保证阻塞时，进程可以被signal唤醒 */
goto interrupted;
error = 0;
*timeo_p = schedule_timeout(*timeo_p); /* sleep本进程，直至满足唤醒条件或者被信号唤醒——因为前面设置了TASK_INTERRUPTIBLE*/
out:
finish_wait(sk_sleep(sk), &wait); /* wait队列的清理工作 */
return error;
interrupted:
error = sock_intr_errno(*timeo_p);
out_err:
*err = error;
goto out;
out_noerr:
*err = 0;
error = 1;
goto out;
}
/* blocks sndbuf producer until at least one byte of free space available */
static int smc_tx_wait_memory(struct smc_sock *smc, int flags)
{
DEFINE_WAIT_FUNC(wait, woken_wake_function);
struct smc_connection *conn = &smc->conn;
struct sock *sk = &smc->sk;
bool noblock;
long timeo;
int rc = 0;
/* similar to sk_stream_wait_memory */
timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
noblock = timeo ? false : true;
add_wait_queue(sk_sleep(sk), &wait);
while (1) {
sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
if (sk->sk_err ||
(sk->sk_shutdown & SEND_SHUTDOWN) ||
conn->local_tx_ctrl.conn_state_flags.peer_done_writing) {
rc = -EPIPE;
break;
}
if (smc_cdc_rxed_any_close(conn)) {
rc = -ECONNRESET;
break;
}
if (!timeo) {
if (noblock)
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
rc = -EAGAIN;
break;
}
if (signal_pending(current)) {
rc = sock_intr_errno(timeo);
break;
}
sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
if (atomic_read(&conn->sndbuf_space))
break; /* at least 1 byte of free space available */
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
sk_wait_event(sk, &timeo,
sk->sk_err ||
(sk->sk_shutdown & SEND_SHUTDOWN) ||
smc_cdc_rxed_any_close(conn) ||
atomic_read(&conn->sndbuf_space),
&wait);
}
remove_wait_queue(sk_sleep(sk), &wait);
return rc;
}
void sk_stream_wait_close(struct sock *sk, long timeout)
{
if (timeout) {
DEFINE_WAIT(wait);
do {
prepare_to_wait(sk_sleep(sk), &wait,
TASK_INTERRUPTIBLE);
if (sk_wait_event(sk, &timeout, !sk_stream_closing(sk)))
break;
} while (!signal_pending(current) && timeout);
finish_wait(sk_sleep(sk), &wait);
}
}
static unsigned int poll(struct file *file, struct socket *sock,
poll_table *wait)
{
struct sock *sk = sock->sk;
u32 mask = 0;
poll_wait(file, sk_sleep(sk), wait);
switch ((int)sock->state) {
case SS_READY:
case SS_CONNECTED:
if (!tipc_sk_port(sk)->congested)
mask |= POLLOUT;
/* fall thru' */
case SS_CONNECTING:
case SS_LISTENING:
if (!skb_queue_empty(&sk->sk_receive_queue))
mask |= (POLLIN | POLLRDNORM);
break;
case SS_DISCONNECTING:
mask = (POLLIN | POLLRDNORM | POLLHUP);
break;
}
return mask;
}
static void set_callbacks(struct socket *socket, struct exa_select_elt *elt)
{
struct sock * sk=socket->sk;
init_waitqueue_entry(&elt->wait,current);
add_wait_queue(sk_sleep(sk), &elt->wait);
}
static int cmtp_session(void *arg)
{
struct cmtp_session *session = arg;
struct sock *sk = session->sock->sk;
struct sk_buff *skb;
wait_queue_t wait;
BT_DBG("session %p", session);
set_user_nice(current, -15);
init_waitqueue_entry(&wait, current);
add_wait_queue(sk_sleep(sk), &wait);
while (1) {
set_current_state(TASK_INTERRUPTIBLE);
if (atomic_read(&session->terminate))
break;
if (sk->sk_state != BT_CONNECTED)
break;
while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
skb_orphan(skb);
if (!skb_linearize(skb))
cmtp_recv_frame(session, skb);
else
kfree_skb(skb);
}
cmtp_process_transmit(session);
schedule();
}
__set_current_state(TASK_RUNNING);
rem
static unsigned int pn_socket_poll(struct file *file, struct socket *sock,
poll_table *wait)
{
struct sock *sk = sock->sk;
struct pep_sock *pn = pep_sk(sk);
unsigned int mask = 0;
poll_wait(file, sk_sleep(sk), wait);
if (sk->sk_state == TCP_CLOSE)
return POLLERR;
if (!skb_queue_empty(&sk->sk_receive_queue))
mask |= POLLIN | POLLRDNORM;
if (!skb_queue_empty(&pn->ctrlreq_queue))
mask |= POLLPRI;
if (!mask && sk->sk_state == TCP_CLOSE_WAIT)
return POLLHUP;
if (sk->sk_state == TCP_ESTABLISHED &&
atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf &&
atomic_read(&pn->tx_credits))
mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
return mask;
}
/*
* Wait for the last received packet to be different from skb
*/
static int wait_for_more_packets(struct sock *sk, int *err, long *timeo_p,
const struct sk_buff *skb)
{
int error;
DEFINE_WAIT_FUNC(wait, receiver_wake_function);
prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
/* Socket errors? */
error = sock_error(sk);
if (error)
goto out_err;
if (sk->sk_receive_queue.prev != skb)
goto out;
/* Socket shut down? */
if (sk->sk_shutdown & RCV_SHUTDOWN)
goto out_noerr;
/* Sequenced packets can come disconnected.
* If so we report the problem
*/
error = -ENOTCONN;
if (connection_based(sk) &&
!(sk->sk_state == TCP_ESTABLISHED || sk->sk_state == TCP_LISTEN))
goto out_err;
/* handle signals */
if (signal_pending(current))
goto interrupted;
error = 0;
*timeo_p = schedule_timeout(*timeo_p);
out:
finish_wait(sk_sleep(sk), &wait);
return error;
interrupted:
error = sock_intr_errno(*timeo_p);
out_err:
*err = error;
goto out;
out_noerr:
*err = 0;
error = 1;
goto out;
}
static void bnep_net_set_mc_list(struct net_device *dev)
{
#ifdef CONFIG_BT_BNEP_MC_FILTER
struct bnep_session *s = netdev_priv(dev);
struct sock *sk = s->sock->sk;
struct bnep_set_filter_req *r;
struct sk_buff *skb;
int size;
BT_DBG("%s mc_count %d", dev->name, netdev_mc_count(dev));
size = sizeof(*r) + (BNEP_MAX_MULTICAST_FILTERS + 1) * ETH_ALEN * 2;
skb = alloc_skb(size, GFP_ATOMIC);
if (!skb) {
BT_ERR("%s Multicast list allocation failed", dev->name);
return;
}
r = (void *) skb->data;
__skb_put(skb, sizeof(*r));
r->type = BNEP_CONTROL;
r->ctrl = BNEP_FILTER_MULTI_ADDR_SET;
if (dev->flags & (IFF_PROMISC | IFF_ALLMULTI)) {
u8 start[ETH_ALEN] = { 0x01 };
/* Request all addresses */
memcpy(__skb_put(skb, ETH_ALEN), start, ETH_ALEN);
memcpy(__skb_put(skb, ETH_ALEN), dev->broadcast, ETH_ALEN);
r->len = htons(ETH_ALEN * 2);
} else {
struct netdev_hw_addr *ha;
int i, len = skb->len;
if (dev->flags & IFF_BROADCAST) {
memcpy(__skb_put(skb, ETH_ALEN), dev->broadcast, ETH_ALEN);
memcpy(__skb_put(skb, ETH_ALEN), dev->broadcast, ETH_ALEN);
}
/* FIXME: We should group addresses here. */
i = 0;
netdev_for_each_mc_addr(ha, dev) {
if (i == BNEP_MAX_MULTICAST_FILTERS)
break;
memcpy(__skb_put(skb, ETH_ALEN), ha->addr, ETH_ALEN);
memcpy(__skb_put(skb, ETH_ALEN), ha->addr, ETH_ALEN);
i++;
}
r->len = htons(skb->len - len);
}
skb_queue_tail(&sk->sk_write_queue, skb);
wake_up_interruptible(sk_sleep(sk));
#endif
}
int svc_change_qos(struct atm_vcc *vcc, struct atm_qos *qos)
{
struct sock *sk = sk_atm(vcc);
DEFINE_WAIT(wait);
set_bit(ATM_VF_WAITING, &vcc->flags);
prepare_to_wait(sk_sleep(sk), &wait, TASK_UNINTERRUPTIBLE);
sigd_enq2(vcc, as_modify, NULL, NULL, &vcc->local, qos, 0);
while (test_bit(ATM_VF_WAITING, &vcc->flags) &&
!test_bit(ATM_VF_RELEASED, &vcc->flags) && sigd) {
schedule();
prepare_to_wait(sk_sleep(sk), &wait, TASK_UNINTERRUPTIBLE);
}
finish_wait(sk_sleep(sk), &wait);
if (!sigd)
return -EUNATCH;
return -sk->sk_err;
}
/**
* dccp_wait_for_ccid - Await CCID send permission
* @sk: socket to wait for
* @delay: timeout in jiffies
* This is used by CCIDs which need to delay the send time in process context.
*/
static int dccp_wait_for_ccid(struct sock *sk, unsigned long delay)
{
DEFINE_WAIT(wait);
long remaining;
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
sk->sk_write_pending++;
release_sock(sk);
remaining = schedule_timeout(delay);
lock_sock(sk);
sk->sk_write_pending--;
finish_wait(sk_sleep(sk), &wait);
if (signal_pending(current) || sk->sk_err)
return -1;
return remaining;
}
static int wait_for_packet(struct sock *sk, int *err, long *timeo_p)
{
int error;
DEFINE_WAIT_FUNC(wait, receiver_wake_function);
prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
error = sock_error(sk);
if (error)
goto out_err;
if (!skb_queue_empty(&sk->sk_receive_queue))
goto out;
if (sk->sk_shutdown & RCV_SHUTDOWN)
goto out_noerr;
error = -ENOTCONN;
if (connection_based(sk) &&
!(sk->sk_state == TCP_ESTABLISHED || sk->sk_state == TCP_LISTEN))
goto out_err;
if (signal_pending(current))
goto interrupted;
error = 0;
*timeo_p = schedule_timeout(*timeo_p);
out:
finish_wait(sk_sleep(sk), &wait);
return error;
interrupted:
error = sock_intr_errno(*timeo_p);
out_err:
*err = error;
goto out;
out_noerr:
*err = 0;
error = 1;
goto out;
}
void
lnet_acceptor_stop(void)
{
if (lnet_acceptor_state.pta_sock == NULL) /* not running */
return;
lnet_acceptor_state.pta_shutdown = 1;
wake_up_all(sk_sleep(lnet_acceptor_state.pta_sock->sk));
/* block until acceptor signals exit */
wait_for_completion(&lnet_acceptor_state.pta_signal);
}
int
lnet_sock_accept(struct socket **newsockp, struct socket *sock)
{
wait_queue_entry_t wait;
struct socket *newsock;
int rc;
/*
* XXX this should add a ref to sock->ops->owner, if
* TCP could be a module
*/
rc = sock_create_lite(PF_PACKET, sock->type, IPPROTO_TCP, &newsock);
if (rc) {
CERROR("Can't allocate socket\n");
return rc;
}
newsock->ops = sock->ops;
rc = sock->ops->accept(sock, newsock, O_NONBLOCK, false);
if (rc == -EAGAIN) {
/* Nothing ready, so wait for activity */
init_waitqueue_entry(&wait, current);
add_wait_queue(sk_sleep(sock->sk), &wait);
set_current_state(TASK_INTERRUPTIBLE);
schedule();
remove_wait_queue(sk_sleep(sock->sk), &wait);
rc = sock->ops->accept(sock, newsock, O_NONBLOCK, false);
}
if (rc)
goto failed;
*newsockp = newsock;
return 0;
failed:
sock_release(newsock);
return rc;
}
static int svc_listen(struct socket *sock, int backlog)
{
DEFINE_WAIT(wait);
struct sock *sk = sock->sk;
struct atm_vcc *vcc = ATM_SD(sock);
int error;
pr_debug("%p\n", vcc);
lock_sock(sk);
/* let server handle listen on unbound sockets */
if (test_bit(ATM_VF_SESSION, &vcc->flags)) {
error = -EINVAL;
goto out;
}
if (test_bit(ATM_VF_LISTEN, &vcc->flags)) {
error = -EADDRINUSE;
goto out;
}
set_bit(ATM_VF_WAITING, &vcc->flags);
sigd_enq(vcc, as_listen, NULL, NULL, &vcc->local);
for (;;) {
prepare_to_wait(sk_sleep(sk), &wait, TASK_UNINTERRUPTIBLE);
if (!test_bit(ATM_VF_WAITING, &vcc->flags) || !sigd)
break;
schedule();
}
finish_wait(sk_sleep(sk), &wait);
if (!sigd) {
error = -EUNATCH;
goto out;
}
set_bit(ATM_VF_LISTEN, &vcc->flags);
vcc_insert_socket(sk);
sk->sk_max_ack_backlog = backlog > 0 ? backlog : ATM_BACKLOG_DEFAULT;
error = -sk->sk_err;
out:
release_sock(sk);
return error;
}
static int send_packet(struct kiocb *iocb, struct socket *sock,
struct msghdr *m, size_t total_len)
{
struct sock *sk = sock->sk;
struct tipc_port *tport = tipc_sk_port(sk);
struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name;
long timeout_val;
int res;
/* Handle implied connection establishment */
if (unlikely(dest))
return send_msg(iocb, sock, m, total_len);
if ((total_len > TIPC_MAX_USER_MSG_SIZE) ||
(m->msg_iovlen > (unsigned)INT_MAX))
return -EMSGSIZE;
if (iocb)
lock_sock(sk);
timeout_val = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
do {
if (unlikely(sock->state != SS_CONNECTED)) {
if (sock->state == SS_DISCONNECTING)
res = -EPIPE;
else
res = -ENOTCONN;
break;
}
res = tipc_send(tport->ref, m->msg_iovlen, m->msg_iov,
total_len);
if (likely(res != -ELINKCONG))
break;
if (timeout_val <= 0L) {
res = timeout_val ? timeout_val : -EWOULDBLOCK;
break;
}
release_sock(sk);
timeout_val = wait_event_interruptible_timeout(*sk_sleep(sk),
(!tport->congested || !tport->connected), timeout_val);
lock_sock(sk);
} while (1);
if (iocb)
release_sock(sk);
return res;
}
static void
kni_sk_write_space(struct sock *sk)
{
wait_queue_head_t *wqueue;
if (!sock_writeable(sk) ||
!test_and_clear_bit(SOCK_ASYNC_NOSPACE,
&sk->sk_socket->flags))
return;
wqueue = sk_sleep(sk);
if (wqueue && waitqueue_active(wqueue))
wake_up_interruptible_poll(
wqueue, POLLOUT | POLLWRNORM | POLLWRBAND);
}
/*
* Wait for a DCCP event.
*
* Note that we don't need to lock the socket, as the upper poll layers
* take care of normal races (between the test and the event) and we don't
* go look at any of the socket buffers directly.
*/
unsigned int dccp_poll(struct file *file, struct socket *sock,
poll_table *wait)
{
unsigned int mask;
struct sock *sk = sock->sk;
sock_poll_wait(file, sk_sleep(sk), wait);
if (sk->sk_state == DCCP_LISTEN)
return inet_csk_listen_poll(sk);
/* Socket is not locked. We are protected from async events
by poll logic and correct handling of state changes
made by another threads is impossible in any case.
*/
mask = 0;
if (sk->sk_err)
mask = POLLERR;
if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED)
mask |= POLLHUP;
if (sk->sk_shutdown & RCV_SHUTDOWN)
mask |= POLLIN | POLLRDNORM | POLLRDHUP;
/* Connected? */
if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) {
if (atomic_read(&sk->sk_rmem_alloc) > 0)
mask |= POLLIN | POLLRDNORM;
if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
if (sk_stream_is_writeable(sk)) {
mask |= POLLOUT | POLLWRNORM;
} else { /* send SIGIO later */
set_bit(SOCK_ASYNC_NOSPACE,
&sk->sk_socket->flags);
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
/* Race breaker. If space is freed after
* wspace test but before the flags are set,
* IO signal will be lost.
*/
if (sk_stream_is_writeable(sk))
mask |= POLLOUT | POLLWRNORM;
}
}
}
return mask;
}
