[patch 30/38] PM: af_iucv power management callbacks.

From: Martin Schwidefsky
Date: Thu Jun 04 2009 - 12:23:31 EST


From: Ursula Braun <ursula.braun@xxxxxxxxxx>

Patch establishes a dummy afiucv-device to make sure af_iucv is
notified as iucv-bus device about suspend/resume.

The PM freeze callback severs all iucv pathes of connected af_iucv sockets.
The PM thaw/restore callback switches the state of all previously connected
sockets to IUCV_DISCONN.

Signed-off-by: Ursula Braun <ursula.braun@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
---
net/iucv/af_iucv.c | 147 +++++++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 144 insertions(+), 3 deletions(-)

Index: linux-2.6/net/iucv/af_iucv.c
===================================================================
--- linux-2.6.orig/net/iucv/af_iucv.c
+++ linux-2.6/net/iucv/af_iucv.c
@@ -1,11 +1,12 @@
/*
- * linux/net/iucv/af_iucv.c
- *
* IUCV protocol stack for Linux on zSeries
*
- * Copyright 2006 IBM Corporation
+ * Copyright IBM Corp. 2006, 2009
*
* Author(s): Jennifer Hunt <jenhunt@xxxxxxxxxx>
+ * Hendrik Brueckner <brueckner@xxxxxxxxxxxxxxxxxx>
+ * PM functions:
+ * Ursula Braun <ursula.braun@xxxxxxxxxx>
*/

#define KMSG_COMPONENT "af_iucv"
@@ -78,6 +79,122 @@ static inline void low_nmcpy(unsigned ch
memcpy(&dst[8], src, 8);
}

+static int afiucv_pm_prepare(struct device *dev)
+{
+#ifdef CONFIG_PM_DEBUG
+ printk(KERN_WARNING "afiucv_pm_prepare\n");
+#endif
+ return 0;
+}
+
+static void afiucv_pm_complete(struct device *dev)
+{
+#ifdef CONFIG_PM_DEBUG
+ printk(KERN_WARNING "afiucv_pm_complete\n");
+#endif
+ return;
+}
+
+/**
+ * afiucv_pm_freeze() - Freeze PM callback
+ * @dev: AFIUCV dummy device
+ *
+ * Sever all established IUCV communication pathes
+ */
+static int afiucv_pm_freeze(struct device *dev)
+{
+ struct iucv_sock *iucv;
+ struct sock *sk;
+ struct hlist_node *node;
+ int err = 0;
+
+#ifdef CONFIG_PM_DEBUG
+ printk(KERN_WARNING "afiucv_pm_freeze\n");
+#endif
+ read_lock(&iucv_sk_list.lock);
+ sk_for_each(sk, node, &iucv_sk_list.head) {
+ iucv = iucv_sk(sk);
+ skb_queue_purge(&iucv->send_skb_q);
+ skb_queue_purge(&iucv->backlog_skb_q);
+ switch (sk->sk_state) {
+ case IUCV_SEVERED:
+ case IUCV_DISCONN:
+ case IUCV_CLOSING:
+ case IUCV_CONNECTED:
+ if (iucv->path) {
+ err = iucv_path_sever(iucv->path, NULL);
+ iucv_path_free(iucv->path);
+ iucv->path = NULL;
+ }
+ break;
+ case IUCV_OPEN:
+ case IUCV_BOUND:
+ case IUCV_LISTEN:
+ case IUCV_CLOSED:
+ default:
+ break;
+ }
+ }
+ read_unlock(&iucv_sk_list.lock);
+ return err;
+}
+
+/**
+ * afiucv_pm_restore_thaw() - Thaw and restore PM callback
+ * @dev: AFIUCV dummy device
+ *
+ * socket clean up after freeze
+ */
+static int afiucv_pm_restore_thaw(struct device *dev)
+{
+ struct iucv_sock *iucv;
+ struct sock *sk;
+ struct hlist_node *node;
+
+#ifdef CONFIG_PM_DEBUG
+ printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
+#endif
+ read_lock(&iucv_sk_list.lock);
+ sk_for_each(sk, node, &iucv_sk_list.head) {
+ iucv = iucv_sk(sk);
+ switch (sk->sk_state) {
+ case IUCV_CONNECTED:
+ sk->sk_err = EPIPE;
+ sk->sk_state = IUCV_DISCONN;
+ sk->sk_state_change(sk);
+ break;
+ case IUCV_DISCONN:
+ case IUCV_SEVERED:
+ case IUCV_CLOSING:
+ case IUCV_LISTEN:
+ case IUCV_BOUND:
+ case IUCV_OPEN:
+ default:
+ break;
+ }
+ }
+ read_unlock(&iucv_sk_list.lock);
+ return 0;
+}
+
+static struct dev_pm_ops afiucv_pm_ops = {
+ .prepare = afiucv_pm_prepare,
+ .complete = afiucv_pm_complete,
+ .freeze = afiucv_pm_freeze,
+ .thaw = afiucv_pm_restore_thaw,
+ .restore = afiucv_pm_restore_thaw,
+};
+
+static struct device_driver af_iucv_driver = {
+ .owner = THIS_MODULE,
+ .name = "afiucv",
+ .bus = &iucv_bus,
+ .pm = &afiucv_pm_ops,
+};
+
+/* dummy device used as trigger for PM functions */
+static struct device *af_iucv_dev;
+
/* Timers */
static void iucv_sock_timeout(unsigned long arg)
{
@@ -1258,8 +1375,30 @@ static int __init afiucv_init(void)
err = sock_register(&iucv_sock_family_ops);
if (err)
goto out_proto;
+ /* establish dummy device */
+ err = driver_register(&af_iucv_driver);
+ if (err)
+ goto out_sock;
+ af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
+ if (!af_iucv_dev) {
+ err = -ENOMEM;
+ goto out_driver;
+ }
+ dev_set_name(af_iucv_dev, "af_iucv");
+ af_iucv_dev->bus = &iucv_bus;
+ af_iucv_dev->parent = iucv_root;
+ af_iucv_dev->release = (void (*)(struct device *))kfree;
+ af_iucv_dev->driver = &af_iucv_driver;
+ err = device_register(af_iucv_dev);
+ if (err)
+ goto out_driver;
+
return 0;

+out_driver:
+ driver_unregister(&af_iucv_driver);
+out_sock:
+ sock_unregister(PF_IUCV);
out_proto:
proto_unregister(&iucv_proto);
out_iucv:
@@ -1270,6 +1409,8 @@ out:

static void __exit afiucv_exit(void)
{
+ device_unregister(af_iucv_dev);
+ driver_unregister(&af_iucv_driver);
sock_unregister(PF_IUCV);
proto_unregister(&iucv_proto);
iucv_unregister(&af_iucv_handler, 0);

--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.

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