VServer 1.9.2 (patch-2.6.8.1-vs1.9.2.diff)
[linux-2.6.git] / net / core / stream.c
index 24a6f72..1e27a57 100644 (file)
@@ -15,6 +15,7 @@
 #include <linux/module.h>
 #include <linux/net.h>
 #include <linux/signal.h>
+#include <linux/tcp.h>
 #include <linux/wait.h>
 #include <net/sock.h>
 
@@ -39,3 +40,248 @@ void sk_stream_write_space(struct sock *sk)
 }
 
 EXPORT_SYMBOL(sk_stream_write_space);
+
+/**
+ * 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);
+
+       while (1) {
+               if (sk->sk_err)
+                       return sock_error(sk);
+               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->sk_sleep, &wait, TASK_INTERRUPTIBLE);
+               sk->sk_write_pending++;
+               if (sk_wait_event(sk, timeo_p,
+                                 !((1 << sk->sk_state) & 
+                                   ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT))))
+                       break;
+               finish_wait(sk->sk_sleep, &wait);
+               sk->sk_write_pending--;
+       }
+       return 0;
+}
+
+EXPORT_SYMBOL(sk_stream_wait_connect);
+
+/**
+ * sk_stream_closing - Return 1 if we still have things to send in our buffers.
+ * @sk - socket to verify
+ */
+static inline int sk_stream_closing(struct sock *sk)
+{
+       return (1 << sk->sk_state) &
+              (TCPF_FIN_WAIT1 | TCPF_CLOSING | TCPF_LAST_ACK);
+}
+
+void sk_stream_wait_close(struct sock *sk, long timeout)
+{
+       if (timeout) {
+               DEFINE_WAIT(wait);
+
+               do {
+                       prepare_to_wait(sk->sk_sleep, &wait,
+                                       TASK_INTERRUPTIBLE);
+                       if (sk_wait_event(sk, &timeout, !sk_stream_closing(sk)))
+                               break;
+               } while (!signal_pending(current) && timeout);
+
+               finish_wait(sk->sk_sleep, &wait);
+       }
+}
+
+EXPORT_SYMBOL(sk_stream_wait_close);
+
+/**
+ * sk_stream_wait_memory - Wait for more memory for a socket
+ * @sk - socket to wait for memory
+ * @timeo_p - for how long
+ */
+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->sk_sleep, &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, &current_timeo, 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->sk_sleep, &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;
+}
+
+EXPORT_SYMBOL(sk_stream_wait_memory);
+
+void sk_stream_rfree(struct sk_buff *skb)
+{
+       struct sock *sk = skb->sk;
+
+       atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
+       sk->sk_forward_alloc += skb->truesize;
+}
+
+EXPORT_SYMBOL(sk_stream_rfree);
+
+int sk_stream_error(struct sock *sk, int flags, int err)
+{
+       if (err == -EPIPE)
+               err = sock_error(sk) ? : -EPIPE;
+       if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
+               send_sig(SIGPIPE, current, 0);
+       return err;
+}
+
+EXPORT_SYMBOL(sk_stream_error);
+
+void __sk_stream_mem_reclaim(struct sock *sk)
+{
+       if (sk->sk_forward_alloc >= SK_STREAM_MEM_QUANTUM) {
+               atomic_sub(sk->sk_forward_alloc / SK_STREAM_MEM_QUANTUM,
+                          sk->sk_prot->memory_allocated);
+               sk->sk_forward_alloc &= SK_STREAM_MEM_QUANTUM - 1;
+               if (*sk->sk_prot->memory_pressure &&
+                   (atomic_read(sk->sk_prot->memory_allocated) <
+                    sk->sk_prot->sysctl_mem[0]))
+                       *sk->sk_prot->memory_pressure = 0;
+       }
+}
+
+EXPORT_SYMBOL(__sk_stream_mem_reclaim);
+
+int sk_stream_mem_schedule(struct sock *sk, int size, int kind)
+{
+       int amt = sk_stream_pages(size);
+
+       sk->sk_forward_alloc += amt * SK_STREAM_MEM_QUANTUM;
+       atomic_add(amt, sk->sk_prot->memory_allocated);
+
+       /* Under limit. */
+       if (atomic_read(sk->sk_prot->memory_allocated) < sk->sk_prot->sysctl_mem[0]) {
+               if (*sk->sk_prot->memory_pressure)
+                       *sk->sk_prot->memory_pressure = 0;
+               return 1;
+       }
+
+       /* Over hard limit. */
+       if (atomic_read(sk->sk_prot->memory_allocated) > sk->sk_prot->sysctl_mem[2]) {
+               sk->sk_prot->enter_memory_pressure();
+               goto suppress_allocation;
+       }
+
+       /* Under pressure. */
+       if (atomic_read(sk->sk_prot->memory_allocated) > sk->sk_prot->sysctl_mem[1])
+               sk->sk_prot->enter_memory_pressure();
+
+       if (kind) {
+               if (atomic_read(&sk->sk_rmem_alloc) < sk->sk_prot->sysctl_rmem[0])
+                       return 1;
+       } else if (sk->sk_wmem_queued < sk->sk_prot->sysctl_wmem[0])
+               return 1;
+
+       if (!*sk->sk_prot->memory_pressure ||
+           sk->sk_prot->sysctl_mem[2] > atomic_read(sk->sk_prot->sockets_allocated) *
+                               sk_stream_pages(sk->sk_wmem_queued +
+                                               atomic_read(&sk->sk_rmem_alloc) +
+                                               sk->sk_forward_alloc))
+               return 1;
+
+suppress_allocation:
+
+       if (!kind) {
+               sk_stream_moderate_sndbuf(sk);
+
+               /* Fail only if socket is _under_ its sndbuf.
+                * In this case we cannot block, so that we have to fail.
+                */
+               if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
+                       return 1;
+       }
+
+       /* Alas. Undo changes. */
+       sk->sk_forward_alloc -= amt * SK_STREAM_MEM_QUANTUM;
+       atomic_sub(amt, sk->sk_prot->memory_allocated);
+       return 0;
+}
+
+EXPORT_SYMBOL(sk_stream_mem_schedule);
+
+void sk_stream_kill_queues(struct sock *sk)
+{
+       /* First the read buffer. */
+       __skb_queue_purge(&sk->sk_receive_queue);
+
+       /* Next, the error queue. */
+       __skb_queue_purge(&sk->sk_error_queue);
+
+       /* Next, the write queue. */
+       BUG_TRAP(skb_queue_empty(&sk->sk_write_queue));
+
+       /* Account for returned memory. */
+       sk_stream_mem_reclaim(sk);
+
+       BUG_TRAP(!sk->sk_wmem_queued);
+       BUG_TRAP(!sk->sk_forward_alloc);
+
+       /* It is _impossible_ for the backlog to contain anything
+        * when we get here.  All user references to this socket
+        * have gone away, only the net layer knows can touch it.
+        */
+}
+
+EXPORT_SYMBOL(sk_stream_kill_queues);