static struct bus_type ccwgroup_bus_type;
-static inline void
+static void
__ccwgroup_remove_symlinks(struct ccwgroup_device *gdev)
{
int i;
* 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)
+{
+ struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
+
+ mutex_lock(&gdev->reg_mutex);
+ __ccwgroup_remove_symlinks(gdev);
+ device_unregister(dev);
+ mutex_unlock(&gdev->reg_mutex);
+}
+
static ssize_t
ccwgroup_ungroup_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
struct ccwgroup_device *gdev;
+ int rc;
gdev = to_ccwgroupdev(dev);
if (gdev->state != CCWGROUP_OFFLINE)
return -EINVAL;
- __ccwgroup_remove_symlinks(gdev);
- device_unregister(dev);
-
+ /* 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 (rc)
+ count = rc;
return count;
}
kfree(gdev);
}
-static inline int
+static int
__ccwgroup_create_symlinks(struct ccwgroup_device *gdev)
{
char str[8];
return 0;
}
-/*
- * try to add a new ccwgroup device for one driver
- * argc and argv[] are a list of bus_id's of devices
- * belonging to the driver.
+/**
+ * ccwgroup_create() - 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
+ * @argc: number of slave devices
+ * @argv: 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 @argv[] and must all
+ * belong to @cdrv.
+ * Returns:
+ * %0 on success and an error code on failure.
+ * Context:
+ * non-atomic
*/
-int
-ccwgroup_create(struct device *root,
- unsigned int creator_id,
- struct ccw_driver *cdrv,
- int argc, char *argv[])
+int ccwgroup_create(struct device *root, unsigned int creator_id,
+ struct ccw_driver *cdrv, int argc, char *argv[])
{
struct ccwgroup_device *gdev;
int i;
return -ENOMEM;
atomic_set(&gdev->onoff, 0);
-
+ mutex_init(&gdev->reg_mutex);
+ mutex_lock(&gdev->reg_mutex);
for (i = 0; i < argc; i++) {
gdev->cdev[i] = get_ccwdev_by_busid(cdrv, argv[i]);
|| gdev->cdev[i]->id.driver_info !=
gdev->cdev[0]->id.driver_info) {
rc = -EINVAL;
- goto free_dev;
+ goto error;
}
/* Don't allow a device to belong to more than one group. */
if (gdev->cdev[i]->dev.driver_data) {
rc = -EINVAL;
- goto free_dev;
+ goto error;
}
gdev->cdev[i]->dev.driver_data = gdev;
}
gdev->cdev[0]->dev.bus_id);
rc = device_register(&gdev->dev);
-
if (rc)
- goto free_dev;
+ goto error;
get_device(&gdev->dev);
rc = device_create_file(&gdev->dev, &dev_attr_ungroup);
rc = __ccwgroup_create_symlinks(gdev);
if (!rc) {
+ mutex_unlock(&gdev->reg_mutex);
put_device(&gdev->dev);
return 0;
}
device_remove_file(&gdev->dev, &dev_attr_ungroup);
device_unregister(&gdev->dev);
error:
- for (i = 0; i < argc; i++)
- if (gdev->cdev[i]) {
- put_device(&gdev->cdev[i]->dev);
- gdev->cdev[i]->dev.driver_data = NULL;
- }
- put_device(&gdev->dev);
- return rc;
-free_dev:
for (i = 0; i < argc; i++)
if (gdev->cdev[i]) {
if (gdev->cdev[i]->dev.driver_data == gdev)
gdev->cdev[i]->dev.driver_data = NULL;
put_device(&gdev->cdev[i]->dev);
}
- kfree(gdev);
+ mutex_unlock(&gdev->reg_mutex);
+ put_device(&gdev->dev);
return rc;
}
if ((ret = device_create_file(dev, &dev_attr_online)))
return ret;
- pr_debug("%s: device %s\n", __func__, gdev->dev.bus_id);
ret = gdrv->probe ? gdrv->probe(gdev) : -ENODEV;
if (ret)
device_remove_file(dev, &dev_attr_online);
gdev = to_ccwgroupdev(dev);
gdrv = to_ccwgroupdrv(dev->driver);
- pr_debug("%s: device %s\n", __func__, gdev->dev.bus_id);
-
device_remove_file(dev, &dev_attr_online);
if (gdrv && gdrv->remove)
.remove = ccwgroup_remove,
};
-int
-ccwgroup_driver_register (struct ccwgroup_driver *cdriver)
+/**
+ * ccwgroup_driver_register() - register a ccw group driver
+ * @cdriver: driver to be registered
+ *
+ * This function is mainly a wrapper around driver_register().
+ */
+int ccwgroup_driver_register(struct ccwgroup_driver *cdriver)
{
/* register our new driver with the core */
cdriver->driver.bus = &ccwgroup_bus_type;
return 1;
}
-void
-ccwgroup_driver_unregister (struct ccwgroup_driver *cdriver)
+/**
+ * ccwgroup_driver_unregister() - deregister a ccw group driver
+ * @cdriver: driver to be deregistered
+ *
+ * This function is mainly a wrapper around driver_unregister().
+ */
+void ccwgroup_driver_unregister(struct ccwgroup_driver *cdriver)
{
struct device *dev;
get_driver(&cdriver->driver);
while ((dev = driver_find_device(&cdriver->driver, NULL, NULL,
__ccwgroup_match_all))) {
- __ccwgroup_remove_symlinks(to_ccwgroupdev(dev));
+ struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
+
+ mutex_lock(&gdev->reg_mutex);
+ __ccwgroup_remove_symlinks(gdev);
device_unregister(dev);
+ mutex_unlock(&gdev->reg_mutex);
put_device(dev);
}
put_driver(&cdriver->driver);
driver_unregister(&cdriver->driver);
}
-int
-ccwgroup_probe_ccwdev(struct ccw_device *cdev)
+/**
+ * ccwgroup_probe_ccwdev() - probe function for slave devices
+ * @cdev: ccw device to be probed
+ *
+ * This is a dummy probe function for ccw devices that are slave devices in
+ * a ccw group device.
+ * Returns:
+ * always %0
+ */
+int ccwgroup_probe_ccwdev(struct ccw_device *cdev)
{
return 0;
}
-static inline struct ccwgroup_device *
+static struct ccwgroup_device *
__ccwgroup_get_gdev_by_cdev(struct ccw_device *cdev)
{
struct ccwgroup_device *gdev;
if (cdev->dev.driver_data) {
gdev = (struct ccwgroup_device *)cdev->dev.driver_data;
if (get_device(&gdev->dev)) {
+ mutex_lock(&gdev->reg_mutex);
if (device_is_registered(&gdev->dev))
return gdev;
+ mutex_unlock(&gdev->reg_mutex);
put_device(&gdev->dev);
}
return NULL;
return NULL;
}
-void
-ccwgroup_remove_ccwdev(struct ccw_device *cdev)
+/**
+ * ccwgroup_remove_ccwdev() - remove function for slave devices
+ * @cdev: ccw device to be removed
+ *
+ * This is a remove function for ccw devices that are slave devices in a ccw
+ * group device. It sets the ccw device offline and also deregisters the
+ * embedding ccw group device.
+ */
+void ccwgroup_remove_ccwdev(struct ccw_device *cdev)
{
struct ccwgroup_device *gdev;
if (gdev) {
__ccwgroup_remove_symlinks(gdev);
device_unregister(&gdev->dev);
+ mutex_unlock(&gdev->reg_mutex);
put_device(&gdev->dev);
}
}
projects / linux-2.6 / blobdiff