[patch 29/38] pm: netiucv power management callbacks.

From: Martin Schwidefsky
Date: Thu Jun 04 2009 - 12:26:58 EST


From: Ursula Braun <ursula.braun@xxxxxxxxxx>

Patch establishes a dummy netiucv device to make sure iucv is notified
about suspend/resume even if netiucv is the only loaded iucv-exploting
module without any real net_device defined.

The PM freeze callback closes all open netiucv connections. Thus the
corresponding iucv path is removed.
The PM thaw/restore callback re-opens previously closed netiucv
connections.

Signed-off-by: Ursula Braun <ursula.braun@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
---
drivers/s390/net/netiucv.c | 115 ++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 109 insertions(+), 6 deletions(-)

Index: linux-2.6/drivers/s390/net/netiucv.c
===================================================================
--- linux-2.6.orig/drivers/s390/net/netiucv.c
+++ linux-2.6/drivers/s390/net/netiucv.c
@@ -1,11 +1,15 @@
/*
* IUCV network driver
*
- * Copyright 2001 IBM Deutschland Entwicklung GmbH, IBM Corporation
- * Author(s): Fritz Elfert (elfert@xxxxxxxxxx, felfert@xxxxxxxxxxxx)
+ * Copyright IBM Corp. 2001, 2009
*
- * Sysfs integration and all bugs therein by Cornelia Huck
- * (cornelia.huck@xxxxxxxxxx)
+ * Author(s):
+ * Original netiucv driver:
+ * Fritz Elfert (elfert@xxxxxxxxxx, felfert@xxxxxxxxxxxx)
+ * Sysfs integration and all bugs therein:
+ * Cornelia Huck (cornelia.huck@xxxxxxxxxx)
+ * PM functions:
+ * Ursula Braun (ursula.braun@xxxxxxxxxx)
*
* Documentation used:
* the source of the original IUCV driver by:
@@ -149,10 +153,27 @@ PRINT_##importance(header "%02x %02x %02

#define PRINTK_HEADER " iucv: " /* for debugging */

+/* dummy device to make sure netiucv_pm functions are called */
+static struct device *netiucv_dev;
+
+static int netiucv_pm_prepare(struct device *);
+static void netiucv_pm_complete(struct device *);
+static int netiucv_pm_freeze(struct device *);
+static int netiucv_pm_restore_thaw(struct device *);
+
+static struct dev_pm_ops netiucv_pm_ops = {
+ .prepare = netiucv_pm_prepare,
+ .complete = netiucv_pm_complete,
+ .freeze = netiucv_pm_freeze,
+ .thaw = netiucv_pm_restore_thaw,
+ .restore = netiucv_pm_restore_thaw,
+};
+
static struct device_driver netiucv_driver = {
.owner = THIS_MODULE,
.name = "netiucv",
.bus = &iucv_bus,
+ .pm = &netiucv_pm_ops,
};

static int netiucv_callback_connreq(struct iucv_path *,
@@ -233,6 +254,7 @@ struct netiucv_priv {
fsm_instance *fsm;
struct iucv_connection *conn;
struct device *dev;
+ int pm_state;
};

/**
@@ -1265,6 +1287,72 @@ static int netiucv_close(struct net_devi
return 0;
}

+static int netiucv_pm_prepare(struct device *dev)
+{
+ IUCV_DBF_TEXT(trace, 3, __func__);
+ return 0;
+}
+
+static void netiucv_pm_complete(struct device *dev)
+{
+ IUCV_DBF_TEXT(trace, 3, __func__);
+ return;
+}
+
+/**
+ * netiucv_pm_freeze() - Freeze PM callback
+ * @dev: netiucv device
+ *
+ * close open netiucv interfaces
+ */
+static int netiucv_pm_freeze(struct device *dev)
+{
+ struct netiucv_priv *priv = dev->driver_data;
+ struct net_device *ndev = NULL;
+ int rc = 0;
+
+ IUCV_DBF_TEXT(trace, 3, __func__);
+ if (priv && priv->conn)
+ ndev = priv->conn->netdev;
+ if (!ndev)
+ goto out;
+ netif_device_detach(ndev);
+ priv->pm_state = fsm_getstate(priv->fsm);
+ rc = netiucv_close(ndev);
+out:
+ return rc;
+}
+
+/**
+ * netiucv_pm_restore_thaw() - Thaw and restore PM callback
+ * @dev: netiucv device
+ *
+ * re-open netiucv interfaces closed during freeze
+ */
+static int netiucv_pm_restore_thaw(struct device *dev)
+{
+ struct netiucv_priv *priv = dev->driver_data;
+ struct net_device *ndev = NULL;
+ int rc = 0;
+
+ IUCV_DBF_TEXT(trace, 3, __func__);
+ if (priv && priv->conn)
+ ndev = priv->conn->netdev;
+ if (!ndev)
+ goto out;
+ switch (priv->pm_state) {
+ case DEV_STATE_RUNNING:
+ case DEV_STATE_STARTWAIT:
+ rc = netiucv_open(ndev);
+ break;
+ default:
+ break;
+ }
+ netif_device_attach(ndev);
+out:
+ return rc;
+}
+
/**
* Start transmission of a packet.
* Called from generic network device layer.
@@ -1731,7 +1819,6 @@ static int netiucv_register_device(struc
struct device *dev = kzalloc(sizeof(struct device), GFP_KERNEL);
int ret;

-
IUCV_DBF_TEXT(trace, 3, __func__);

if (dev) {
@@ -2100,6 +2187,7 @@ static void __exit netiucv_exit(void)
netiucv_unregister_device(dev);
}

+ device_unregister(netiucv_dev);
driver_unregister(&netiucv_driver);
iucv_unregister(&netiucv_handler, 1);
iucv_unregister_dbf_views();
@@ -2125,10 +2213,25 @@ static int __init netiucv_init(void)
IUCV_DBF_TEXT_(setup, 2, "ret %d from driver_register\n", rc);
goto out_iucv;
}
-
+ /* establish dummy device */
+ netiucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
+ if (!netiucv_dev) {
+ rc = -ENOMEM;
+ goto out_driver;
+ }
+ dev_set_name(netiucv_dev, "netiucv");
+ netiucv_dev->bus = &iucv_bus;
+ netiucv_dev->parent = iucv_root;
+ netiucv_dev->release = (void (*)(struct device *))kfree;
+ netiucv_dev->driver = &netiucv_driver;
+ rc = device_register(netiucv_dev);
+ if (rc)
+ goto out_driver;
netiucv_banner();
return rc;

+out_driver:
+ driver_unregister(&netiucv_driver);
out_iucv:
iucv_unregister(&netiucv_handler, 1);
out_dbf:

--
blue skies,
Martin.

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

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