1 files changed, 99 insertions, 109 deletions

diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index 4f1989d27b1..e443b0d0b23 100644
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -1,7 +1,7 @@
 /*
  *  bus driver for ccwgroup
  *
- *  Copyright IBM Corp. 2002, 2009
+ *  Copyright IBM Corp. 2002, 2012
  *
  *  Author(s): Arnd Bergmann (arndb@de.ibm.com)
  *	       Cornelia Huck (cornelia.huck@de.ibm.com)
@@ -15,10 +15,13 @@
 #include <linux/ctype.h>
 #include <linux/dcache.h>
 
+#include <asm/cio.h>
 #include <asm/ccwdev.h>
 #include <asm/ccwgroup.h>
 
-#define CCW_BUS_ID_SIZE		20
+#include "device.h"
+
+#define CCW_BUS_ID_SIZE		10
 
 /* In Linux 2.4, we had a channel device layer called "chandev"
  * that did all sorts of obscure stuff for networking devices.
@@ -27,19 +30,6 @@
  * to devices that use multiple subchannels.
  */
 
-/* a device matches a driver if all its slave devices match the same
- * entry of the driver */
-static int ccwgroup_bus_match(struct device *dev, struct device_driver * drv)
-{
-	struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
-	struct ccwgroup_driver *gdrv = to_ccwgroupdrv(drv);
-
-	if (gdev->creator_id == gdrv->driver_id)
-		return 1;
-
-	return 0;
-}
-
 static struct bus_type ccwgroup_bus_type;
 
 static void __ccwgroup_remove_symlinks(struct ccwgroup_device *gdev)
@@ -75,10 +65,18 @@ static void __ccwgroup_remove_cdev_refs(struct ccwgroup_device *gdev)
 	}
 }
 
-static int ccwgroup_set_online(struct ccwgroup_device *gdev)
+/**
+ * ccwgroup_set_online() - enable a ccwgroup device
+ * @gdev: target ccwgroup device
+ *
+ * This function attempts to put the ccwgroup device into the online state.
+ * Returns:
+ *  %0 on success and a negative error value on failure.
+ */
+int ccwgroup_set_online(struct ccwgroup_device *gdev)
 {
 	struct ccwgroup_driver *gdrv = to_ccwgroupdrv(gdev->dev.driver);
-	int ret = 0;
+	int ret = -EINVAL;
 
 	if (atomic_cmpxchg(&gdev->onoff, 0, 1) != 0)
 		return -EAGAIN;
@@ -94,11 +92,20 @@ out:
 	atomic_set(&gdev->onoff, 0);
 	return ret;
 }
+EXPORT_SYMBOL(ccwgroup_set_online);
 
-static int ccwgroup_set_offline(struct ccwgroup_device *gdev)
+/**
+ * ccwgroup_set_offline() - disable a ccwgroup device
+ * @gdev: target ccwgroup device
+ *
+ * This function attempts to put the ccwgroup device into the offline state.
+ * Returns:
+ *  %0 on success and a negative error value on failure.
+ */
+int ccwgroup_set_offline(struct ccwgroup_device *gdev)
 {
 	struct ccwgroup_driver *gdrv = to_ccwgroupdrv(gdev->dev.driver);
-	int ret = 0;
+	int ret = -EINVAL;
 
 	if (atomic_cmpxchg(&gdev->onoff, 0, 1) != 0)
 		return -EAGAIN;
@@ -114,22 +121,23 @@ out:
 	atomic_set(&gdev->onoff, 0);
 	return ret;
 }
+EXPORT_SYMBOL(ccwgroup_set_offline);
 
 static ssize_t ccwgroup_online_store(struct device *dev,
 				     struct device_attribute *attr,
 				     const char *buf, size_t count)
 {
 	struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
-	struct ccwgroup_driver *gdrv = to_ccwgroupdrv(dev->driver);
 	unsigned long value;
 	int ret;
 
-	if (!dev->driver)
-		return -EINVAL;
-	if (!try_module_get(gdrv->driver.owner))
-		return -EINVAL;
+	device_lock(dev);
+	if (!dev->driver) {
+		ret = -EINVAL;
+		goto out;
+	}
 
-	ret = strict_strtoul(buf, 0, &value);
+	ret = kstrtoul(buf, 0, &value);
 	if (ret)
 		goto out;
 
@@ -140,7 +148,7 @@ static ssize_t ccwgroup_online_store(struct device *dev,
 	else
 		ret = -EINVAL;
 out:
-	module_put(gdrv->driver.owner);
+	device_unlock(dev);
 	return (ret == 0) ? count : ret;
 }
 
@@ -160,14 +168,12 @@ static ssize_t ccwgroup_online_show(struct device *dev,
  * Provide an 'ungroup' attribute so the user can remove group devices no
  * longer needed or accidentially created. Saves memory :)
  */
-static void ccwgroup_ungroup_callback(struct device *dev)
+static void ccwgroup_ungroup(struct ccwgroup_device *gdev)
 {
-	struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
-
 	mutex_lock(&gdev->reg_mutex);
 	if (device_is_registered(&gdev->dev)) {
 		__ccwgroup_remove_symlinks(gdev);
-		device_unregister(dev);
+		device_unregister(&gdev->dev);
 		__ccwgroup_remove_cdev_refs(gdev);
 	}
 	mutex_unlock(&gdev->reg_mutex);
@@ -178,7 +184,7 @@ static ssize_t ccwgroup_ungroup_store(struct device *dev,
 				      const char *buf, size_t count)
 {
 	struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
-	int rc;
+	int rc = 0;
 
 	/* Prevent concurrent online/offline processing and ungrouping. */
 	if (atomic_cmpxchg(&gdev->onoff, 0, 1) != 0)
@@ -187,15 +193,15 @@ static ssize_t ccwgroup_ungroup_store(struct device *dev,
 		rc = -EINVAL;
 		goto out;
 	}
-	/* Note that we cannot unregister the device from one of its
-	 * attribute methods, so we have to use this roundabout approach.
-	 */
-	rc = device_schedule_callback(dev, ccwgroup_ungroup_callback);
+
+	if (device_remove_file_self(dev, attr))
+		ccwgroup_ungroup(gdev);
+	else
+		rc = -ENODEV;
 out:
 	if (rc) {
-		if (rc != -EAGAIN)
-			/* Release onoff "lock" when ungrouping failed. */
-			atomic_set(&gdev->onoff, 0);
+		/* Release onoff "lock" when ungrouping failed. */
+		atomic_set(&gdev->onoff, 0);
 		return rc;
 	}
 	return count;
@@ -216,6 +222,15 @@ static const struct attribute_group *ccwgroup_attr_groups[] = {
 	NULL,
 };
 
+static void ccwgroup_ungroup_workfn(struct work_struct *work)
+{
+	struct ccwgroup_device *gdev =
+		container_of(work, struct ccwgroup_device, ungroup_work);
+
+	ccwgroup_ungroup(gdev);
+	put_device(&gdev->dev);
+}
+
 static void ccwgroup_release(struct device *dev)
 {
 	kfree(to_ccwgroupdev(dev));
@@ -254,9 +269,10 @@ static int __ccwgroup_create_symlinks(struct ccwgroup_device *gdev)
 	return 0;
 }
 
-static int __get_next_bus_id(const char **buf, char *bus_id)
+static int __get_next_id(const char **buf, struct ccw_dev_id *id)
 {
-	int rc, len;
+	unsigned int cssid, ssid, devno;
+	int ret = 0, len;
 	char *start, *end;
 
 	start = (char *)*buf;
@@ -271,49 +287,40 @@ static int __get_next_bus_id(const char **buf, char *bus_id)
 		len = end - start + 1;
 		end++;
 	}
-	if (len < CCW_BUS_ID_SIZE) {
-		strlcpy(bus_id, start, len);
-		rc = 0;
+	if (len <= CCW_BUS_ID_SIZE) {
+		if (sscanf(start, "%2x.%1x.%04x", &cssid, &ssid, &devno) != 3)
+			ret = -EINVAL;
 	} else
-		rc = -EINVAL;
-	*buf = end;
-	return rc;
-}
-
-static int __is_valid_bus_id(char bus_id[CCW_BUS_ID_SIZE])
-{
-	int cssid, ssid, devno;
+		ret = -EINVAL;
 
-	/* Must be of form %x.%x.%04x */
-	if (sscanf(bus_id, "%x.%1x.%04x", &cssid, &ssid, &devno) != 3)
-		return 0;
-	return 1;
+	if (!ret) {
+		id->ssid = ssid;
+		id->devno = devno;
+	}
+	*buf = end;
+	return ret;
 }
 
 /**
- * ccwgroup_create_from_string() - create and register a ccw group device
- * @root: parent device for the new device
- * @creator_id: identifier of creating driver
- * @cdrv: ccw driver of slave devices
+ * ccwgroup_create_dev() - create and register a ccw group device
+ * @parent: parent device for the new device
+ * @gdrv: driver for the new group device
  * @num_devices: number of slave devices
  * @buf: buffer containing comma separated bus ids of slave devices
  *
- * Create and register a new ccw group device as a child of @root. Slave
- * devices are obtained from the list of bus ids given in @buf and must all
- * belong to @cdrv.
+ * Create and register a new ccw group device as a child of @parent. Slave
+ * devices are obtained from the list of bus ids given in @buf.
  * Returns:
  *  %0 on success and an error code on failure.
  * Context:
  *  non-atomic
  */
-int ccwgroup_create_from_string(struct device *root, unsigned int creator_id,
-				struct ccw_driver *cdrv, int num_devices,
-				const char *buf)
+int ccwgroup_create_dev(struct device *parent, struct ccwgroup_driver *gdrv,
+			int num_devices, const char *buf)
 {
 	struct ccwgroup_device *gdev;
+	struct ccw_dev_id dev_id;
 	int rc, i;
-	char tmp_bus_id[CCW_BUS_ID_SIZE];
-	const char *curr_buf;
 
 	gdev = kzalloc(sizeof(*gdev) + num_devices * sizeof(gdev->cdev[0]),
 		       GFP_KERNEL);
@@ -323,29 +330,25 @@ int ccwgroup_create_from_string(struct device *root, unsigned int creator_id,
 	atomic_set(&gdev->onoff, 0);
 	mutex_init(&gdev->reg_mutex);
 	mutex_lock(&gdev->reg_mutex);
-	gdev->creator_id = creator_id;
+	INIT_WORK(&gdev->ungroup_work, ccwgroup_ungroup_workfn);
 	gdev->count = num_devices;
 	gdev->dev.bus = &ccwgroup_bus_type;
-	gdev->dev.parent = root;
+	gdev->dev.parent = parent;
 	gdev->dev.release = ccwgroup_release;
 	device_initialize(&gdev->dev);
 
-	curr_buf = buf;
-	for (i = 0; i < num_devices && curr_buf; i++) {
-		rc = __get_next_bus_id(&curr_buf, tmp_bus_id);
+	for (i = 0; i < num_devices && buf; i++) {
+		rc = __get_next_id(&buf, &dev_id);
 		if (rc != 0)
 			goto error;
-		if (!__is_valid_bus_id(tmp_bus_id)) {
-			rc = -EINVAL;
-			goto error;
-		}
-		gdev->cdev[i] = get_ccwdev_by_busid(cdrv, tmp_bus_id);
+		gdev->cdev[i] = get_ccwdev_by_dev_id(&dev_id);
 		/*
 		 * All devices have to be of the same type in
 		 * order to be grouped.
 		 */
-		if (!gdev->cdev[i]
-		    || gdev->cdev[i]->id.driver_info !=
+		if (!gdev->cdev[i] || !gdev->cdev[i]->drv ||
+		    gdev->cdev[i]->drv != gdev->cdev[0]->drv ||
+		    gdev->cdev[i]->id.driver_info !=
 		    gdev->cdev[0]->id.driver_info) {
 			rc = -EINVAL;
 			goto error;
@@ -361,18 +364,25 @@ int ccwgroup_create_from_string(struct device *root, unsigned int creator_id,
 		spin_unlock_irq(gdev->cdev[i]->ccwlock);
 	}
 	/* Check for sufficient number of bus ids. */
-	if (i < num_devices && !curr_buf) {
+	if (i < num_devices) {
 		rc = -EINVAL;
 		goto error;
 	}
 	/* Check for trailing stuff. */
-	if (i == num_devices && strlen(curr_buf) > 0) {
+	if (i == num_devices && strlen(buf) > 0) {
 		rc = -EINVAL;
 		goto error;
 	}
 
 	dev_set_name(&gdev->dev, "%s", dev_name(&gdev->cdev[0]->dev));
 	gdev->dev.groups = ccwgroup_attr_groups;
+
+	if (gdrv) {
+		gdev->dev.driver = &gdrv->driver;
+		rc = gdrv->setup ? gdrv->setup(gdev) : 0;
+		if (rc)
+			goto error;
+	}
 	rc = device_add(&gdev->dev);
 	if (rc)
 		goto error;
@@ -397,15 +407,17 @@ error:
 	put_device(&gdev->dev);
 	return rc;
 }
-EXPORT_SYMBOL(ccwgroup_create_from_string);
+EXPORT_SYMBOL(ccwgroup_create_dev);
 
 static int ccwgroup_notifier(struct notifier_block *nb, unsigned long action,
 			     void *data)
 {
-	struct device *dev = data;
+	struct ccwgroup_device *gdev = to_ccwgroupdev(data);
 
-	if (action == BUS_NOTIFY_UNBIND_DRIVER)
-		device_schedule_callback(dev, ccwgroup_ungroup_callback);
+	if (action == BUS_NOTIFY_UNBIND_DRIVER) {
+		get_device(&gdev->dev);
+		schedule_work(&gdev->ungroup_work);
+	}
 
 	return NOTIFY_OK;
 }
@@ -440,14 +452,6 @@ module_exit(cleanup_ccwgroup);
 
 /************************** driver stuff ******************************/
 
-static int ccwgroup_probe(struct device *dev)
-{
-	struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
-	struct ccwgroup_driver *gdrv = to_ccwgroupdrv(dev->driver);
-
-	return gdrv->probe ? gdrv->probe(gdev) : -ENODEV;
-}
-
 static int ccwgroup_remove(struct device *dev)
 {
 	struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
@@ -542,8 +546,6 @@ static const struct dev_pm_ops ccwgroup_pm_ops = {
 
 static struct bus_type ccwgroup_bus_type = {
 	.name   = "ccwgroup",
-	.match  = ccwgroup_bus_match,
-	.probe  = ccwgroup_probe,
 	.remove = ccwgroup_remove,
 	.shutdown = ccwgroup_shutdown,
 	.pm = &ccwgroup_pm_ops,
@@ -580,19 +582,13 @@ void ccwgroup_driver_unregister(struct ccwgroup_driver *cdriver)
 	struct device *dev;
 
 	/* We don't want ccwgroup devices to live longer than their driver. */
-	get_driver(&cdriver->driver);
 	while ((dev = driver_find_device(&cdriver->driver, NULL, NULL,
 					 __ccwgroup_match_all))) {
 		struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
 
-		mutex_lock(&gdev->reg_mutex);
-		__ccwgroup_remove_symlinks(gdev);
-		device_unregister(dev);
-		__ccwgroup_remove_cdev_refs(gdev);
-		mutex_unlock(&gdev->reg_mutex);
+		ccwgroup_ungroup(gdev);
 		put_device(dev);
 	}
-	put_driver(&cdriver->driver);
 	driver_unregister(&cdriver->driver);
 }
 EXPORT_SYMBOL(ccwgroup_driver_unregister);
@@ -637,13 +633,7 @@ void ccwgroup_remove_ccwdev(struct ccw_device *cdev)
 	get_device(&gdev->dev);
 	spin_unlock_irq(cdev->ccwlock);
 	/* Unregister group device. */
-	mutex_lock(&gdev->reg_mutex);
-	if (device_is_registered(&gdev->dev)) {
-		__ccwgroup_remove_symlinks(gdev);
-		device_unregister(&gdev->dev);
-		__ccwgroup_remove_cdev_refs(gdev);
-	}
-	mutex_unlock(&gdev->reg_mutex);
+	ccwgroup_ungroup(gdev);
 	/* Release ccwgroup device reference for local processing. */
 	put_device(&gdev->dev);
 }