1 files changed, 261 insertions, 0 deletions

diff --git a/net/rxrpc/krxiod.c b/net/rxrpc/krxiod.c
new file mode 100644
index 000000000000..2b537f425a17
--- /dev/null
+++ b/net/rxrpc/krxiod.c
@@ -0,0 +1,261 @@
+/* krxiod.c: Rx I/O daemon
+ *
+ * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/sched.h>
+#include <linux/completion.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <rxrpc/krxiod.h>
+#include <rxrpc/transport.h>
+#include <rxrpc/peer.h>
+#include <rxrpc/call.h>
+#include "internal.h"
+
+static DECLARE_WAIT_QUEUE_HEAD(rxrpc_krxiod_sleepq);
+static DECLARE_COMPLETION(rxrpc_krxiod_dead);
+
+static atomic_t rxrpc_krxiod_qcount = ATOMIC_INIT(0);
+
+static LIST_HEAD(rxrpc_krxiod_transportq);
+static DEFINE_SPINLOCK(rxrpc_krxiod_transportq_lock);
+
+static LIST_HEAD(rxrpc_krxiod_callq);
+static DEFINE_SPINLOCK(rxrpc_krxiod_callq_lock);
+
+static volatile int rxrpc_krxiod_die;
+
+/*****************************************************************************/
+/*
+ * Rx I/O daemon
+ */
+static int rxrpc_krxiod(void *arg)
+{
+        DECLARE_WAITQUEUE(krxiod,current);
+
+        printk("Started krxiod %d\n",current->pid);
+
+        daemonize("krxiod");
+
+        /* loop around waiting for work to do */
+        do {
+                /* wait for work or to be told to exit */
+                _debug("### Begin Wait");
+                if (!atomic_read(&rxrpc_krxiod_qcount)) {
+                        set_current_state(TASK_INTERRUPTIBLE);
+
+                        add_wait_queue(&rxrpc_krxiod_sleepq, &krxiod);
+
+                        for (;;) {
+                                set_current_state(TASK_INTERRUPTIBLE);
+                                if (atomic_read(&rxrpc_krxiod_qcount) ||
+                                    rxrpc_krxiod_die ||
+                                    signal_pending(current))
+                                        break;
+
+                                schedule();
+                        }
+
+                        remove_wait_queue(&rxrpc_krxiod_sleepq, &krxiod);
+                        set_current_state(TASK_RUNNING);
+                }
+                _debug("### End Wait");
+
+                /* do work if been given some to do */
+                _debug("### Begin Work");
+
+                /* see if there's a transport in need of attention */
+                if (!list_empty(&rxrpc_krxiod_transportq)) {
+                        struct rxrpc_transport *trans = NULL;
+
+                        spin_lock_irq(&rxrpc_krxiod_transportq_lock);
+
+                        if (!list_empty(&rxrpc_krxiod_transportq)) {
+                                trans = list_entry(
+                                        rxrpc_krxiod_transportq.next,
+                                        struct rxrpc_transport,
+                                        krxiodq_link);
+
+                                list_del_init(&trans->krxiodq_link);
+                                atomic_dec(&rxrpc_krxiod_qcount);
+
+                                /* make sure it hasn't gone away and doesn't go
+                                 * away */
+                                if (atomic_read(&trans->usage)>0)
+                                        rxrpc_get_transport(trans);
+                                else
+                                        trans = NULL;
+                        }
+
+                        spin_unlock_irq(&rxrpc_krxiod_transportq_lock);
+
+                        if (trans) {
+                                rxrpc_trans_receive_packet(trans);
+                                rxrpc_put_transport(trans);
+                        }
+                }
+
+                /* see if there's a call in need of attention */
+                if (!list_empty(&rxrpc_krxiod_callq)) {
+                        struct rxrpc_call *call = NULL;
+
+                        spin_lock_irq(&rxrpc_krxiod_callq_lock);
+
+                        if (!list_empty(&rxrpc_krxiod_callq)) {
+                                call = list_entry(rxrpc_krxiod_callq.next,
+                                                  struct rxrpc_call,
+                                                  rcv_krxiodq_lk);
+                                list_del_init(&call->rcv_krxiodq_lk);
+                                atomic_dec(&rxrpc_krxiod_qcount);
+
+                                /* make sure it hasn't gone away and doesn't go
+                                 * away */
+                                if (atomic_read(&call->usage) > 0) {
+                                        _debug("@@@ KRXIOD"
+                                               " Begin Attend Call %p", call);
+                                        rxrpc_get_call(call);
+                                }
+                                else {
+                                        call = NULL;
+                                }
+                        }
+
+                        spin_unlock_irq(&rxrpc_krxiod_callq_lock);
+
+                        if (call) {
+                                rxrpc_call_do_stuff(call);
+                                rxrpc_put_call(call);
+                                _debug("@@@ KRXIOD End Attend Call %p", call);
+                        }
+                }
+
+                _debug("### End Work");
+
+                try_to_freeze(PF_FREEZE);
+
+                /* discard pending signals */
+                rxrpc_discard_my_signals();
+
+        } while (!rxrpc_krxiod_die);
+
+        /* and that's all */
+        complete_and_exit(&rxrpc_krxiod_dead, 0);
+
+} /* end rxrpc_krxiod() */
+
+/*****************************************************************************/
+/*
+ * start up a krxiod daemon
+ */
+int __init rxrpc_krxiod_init(void)
+{
+        return kernel_thread(rxrpc_krxiod, NULL, 0);
+
+} /* end rxrpc_krxiod_init() */
+
+/*****************************************************************************/
+/*
+ * kill the krxiod daemon and wait for it to complete
+ */
+void rxrpc_krxiod_kill(void)
+{
+        rxrpc_krxiod_die = 1;
+        wake_up_all(&rxrpc_krxiod_sleepq);
+        wait_for_completion(&rxrpc_krxiod_dead);
+
+} /* end rxrpc_krxiod_kill() */
+
+/*****************************************************************************/
+/*
+ * queue a transport for attention by krxiod
+ */
+void rxrpc_krxiod_queue_transport(struct rxrpc_transport *trans)
+{
+        unsigned long flags;
+
+        _enter("");
+
+        if (list_empty(&trans->krxiodq_link)) {
+                spin_lock_irqsave(&rxrpc_krxiod_transportq_lock, flags);
+
+                if (list_empty(&trans->krxiodq_link)) {
+                        if (atomic_read(&trans->usage) > 0) {
+                                list_add_tail(&trans->krxiodq_link,
+                                              &rxrpc_krxiod_transportq);
+                                atomic_inc(&rxrpc_krxiod_qcount);
+                        }
+                }
+
+                spin_unlock_irqrestore(&rxrpc_krxiod_transportq_lock, flags);
+                wake_up_all(&rxrpc_krxiod_sleepq);
+        }
+
+        _leave("");
+
+} /* end rxrpc_krxiod_queue_transport() */
+
+/*****************************************************************************/
+/*
+ * dequeue a transport from krxiod's attention queue
+ */
+void rxrpc_krxiod_dequeue_transport(struct rxrpc_transport *trans)
+{
+        unsigned long flags;
+
+        _enter("");
+
+        spin_lock_irqsave(&rxrpc_krxiod_transportq_lock, flags);
+        if (!list_empty(&trans->krxiodq_link)) {
+                list_del_init(&trans->krxiodq_link);
+                atomic_dec(&rxrpc_krxiod_qcount);
+        }
+        spin_unlock_irqrestore(&rxrpc_krxiod_transportq_lock, flags);
+
+        _leave("");
+
+} /* end rxrpc_krxiod_dequeue_transport() */
+
+/*****************************************************************************/
+/*
+ * queue a call for attention by krxiod
+ */
+void rxrpc_krxiod_queue_call(struct rxrpc_call *call)
+{
+        unsigned long flags;
+
+        if (list_empty(&call->rcv_krxiodq_lk)) {
+                spin_lock_irqsave(&rxrpc_krxiod_callq_lock, flags);
+                if (atomic_read(&call->usage) > 0) {
+                        list_add_tail(&call->rcv_krxiodq_lk,
+                                      &rxrpc_krxiod_callq);
+                        atomic_inc(&rxrpc_krxiod_qcount);
+                }
+                spin_unlock_irqrestore(&rxrpc_krxiod_callq_lock, flags);
+        }
+        wake_up_all(&rxrpc_krxiod_sleepq);
+
+} /* end rxrpc_krxiod_queue_call() */
+
+/*****************************************************************************/
+/*
+ * dequeue a call from krxiod's attention queue
+ */
+void rxrpc_krxiod_dequeue_call(struct rxrpc_call *call)
+{
+        unsigned long flags;
+
+        spin_lock_irqsave(&rxrpc_krxiod_callq_lock, flags);
+        if (!list_empty(&call->rcv_krxiodq_lk)) {
+                list_del_init(&call->rcv_krxiodq_lk);
+                atomic_dec(&rxrpc_krxiod_qcount);
+        }
+        spin_unlock_irqrestore(&rxrpc_krxiod_callq_lock, flags);
+
+} /* end rxrpc_krxiod_dequeue_call() */