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15#include <linux/module.h>
16#include <linux/net.h>
17#include <linux/signal.h>
18#include <linux/tcp.h>
19#include <linux/wait.h>
20#include <net/sock.h>
21
22
23
24
25
26
27
28void sk_stream_write_space(struct sock *sk)
29{
30 struct socket *sock = sk->sk_socket;
31 struct socket_wq *wq;
32
33 if (sk_stream_is_writeable(sk) && sock) {
34 clear_bit(SOCK_NOSPACE, &sock->flags);
35
36 rcu_read_lock();
37 wq = rcu_dereference(sk->sk_wq);
38 if (wq_has_sleeper(wq))
39 wake_up_interruptible_poll(&wq->wait, POLLOUT |
40 POLLWRNORM | POLLWRBAND);
41 if (wq && wq->fasync_list && !(sk->sk_shutdown & SEND_SHUTDOWN))
42 sock_wake_async(sock, SOCK_WAKE_SPACE, POLL_OUT);
43 rcu_read_unlock();
44 }
45}
46EXPORT_SYMBOL(sk_stream_write_space);
47
48
49
50
51
52
53
54
55int sk_stream_wait_connect(struct sock *sk, long *timeo_p)
56{
57 struct task_struct *tsk = current;
58 DEFINE_WAIT(wait);
59 int done;
60
61 do {
62 int err = sock_error(sk);
63 if (err)
64 return err;
65 if ((1 << sk->sk_state) & ~(TCPF_SYN_SENT | TCPF_SYN_RECV))
66 return -EPIPE;
67 if (!*timeo_p)
68 return -EAGAIN;
69 if (signal_pending(tsk))
70 return sock_intr_errno(*timeo_p);
71
72 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
73 sk->sk_write_pending++;
74 done = sk_wait_event(sk, timeo_p,
75 !sk->sk_err &&
76 !((1 << sk->sk_state) &
77 ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)));
78 finish_wait(sk_sleep(sk), &wait);
79 sk->sk_write_pending--;
80 } while (!done);
81 return 0;
82}
83EXPORT_SYMBOL(sk_stream_wait_connect);
84
85
86
87
88
89static inline int sk_stream_closing(struct sock *sk)
90{
91 return (1 << sk->sk_state) &
92 (TCPF_FIN_WAIT1 | TCPF_CLOSING | TCPF_LAST_ACK);
93}
94
95void sk_stream_wait_close(struct sock *sk, long timeout)
96{
97 if (timeout) {
98 DEFINE_WAIT(wait);
99
100 do {
101 prepare_to_wait(sk_sleep(sk), &wait,
102 TASK_INTERRUPTIBLE);
103 if (sk_wait_event(sk, &timeout, !sk_stream_closing(sk)))
104 break;
105 } while (!signal_pending(current) && timeout);
106
107 finish_wait(sk_sleep(sk), &wait);
108 }
109}
110EXPORT_SYMBOL(sk_stream_wait_close);
111
112
113
114
115
116
117int sk_stream_wait_memory(struct sock *sk, long *timeo_p)
118{
119 int err = 0;
120 long vm_wait = 0;
121 long current_timeo = *timeo_p;
122 bool noblock = (*timeo_p ? false : true);
123 DEFINE_WAIT(wait);
124
125 if (sk_stream_memory_free(sk))
126 current_timeo = vm_wait = (prandom_u32() % (HZ / 5)) + 2;
127
128 while (1) {
129 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
130
131 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
132
133 if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
134 goto do_error;
135 if (!*timeo_p) {
136 if (noblock)
137 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
138 goto do_nonblock;
139 }
140 if (signal_pending(current))
141 goto do_interrupted;
142 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
143 if (sk_stream_memory_free(sk) && !vm_wait)
144 break;
145
146 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
147 sk->sk_write_pending++;
148 sk_wait_event(sk, ¤t_timeo, sk->sk_err ||
149 (sk->sk_shutdown & SEND_SHUTDOWN) ||
150 (sk_stream_memory_free(sk) &&
151 !vm_wait));
152 sk->sk_write_pending--;
153
154 if (vm_wait) {
155 vm_wait -= current_timeo;
156 current_timeo = *timeo_p;
157 if (current_timeo != MAX_SCHEDULE_TIMEOUT &&
158 (current_timeo -= vm_wait) < 0)
159 current_timeo = 0;
160 vm_wait = 0;
161 }
162 *timeo_p = current_timeo;
163 }
164out:
165 finish_wait(sk_sleep(sk), &wait);
166 return err;
167
168do_error:
169 err = -EPIPE;
170 goto out;
171do_nonblock:
172 err = -EAGAIN;
173 goto out;
174do_interrupted:
175 err = sock_intr_errno(*timeo_p);
176 goto out;
177}
178EXPORT_SYMBOL(sk_stream_wait_memory);
179
180int sk_stream_error(struct sock *sk, int flags, int err)
181{
182 if (err == -EPIPE)
183 err = sock_error(sk) ? : -EPIPE;
184 if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
185 send_sig(SIGPIPE, current, 0);
186 return err;
187}
188EXPORT_SYMBOL(sk_stream_error);
189
190void sk_stream_kill_queues(struct sock *sk)
191{
192
193 __skb_queue_purge(&sk->sk_receive_queue);
194
195
196 __skb_queue_purge(&sk->sk_error_queue);
197
198
199 WARN_ON(!skb_queue_empty(&sk->sk_write_queue));
200
201
202 sk_mem_reclaim(sk);
203
204 WARN_ON(sk->sk_wmem_queued);
205 WARN_ON(sk->sk_forward_alloc);
206
207
208
209
210
211}
212EXPORT_SYMBOL(sk_stream_kill_queues);
213