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Commit 2ee97caf authored by Cornelia Huck's avatar Cornelia Huck Committed by Greg Kroah-Hartman
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Driver core: check return code of sysfs_create_link() 



Check for return value of sysfs_create_link() in device_add() and
device_rename().  Add helper functions device_add_class_symlinks() and
device_remove_class_symlinks() to make the code easier to read.

[akpm@linux-foundation.org: fix unused var warnings]

Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: default avatarJeff Garzik <jeff@garzik.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent be388494

drivers/base/core.c

+105 −40
Original line number Diff line number Diff line
@@ -660,6 +660,82 @@ static int setup_parent(struct device *dev, struct device *parent) 
	return 0;

}



static int device_add_class_symlinks(struct device *dev)

{

	int error;



	if (!dev->class)

		return 0;

	error = sysfs_create_link(&dev->kobj, &dev->class->subsys.kobj,

				  "subsystem");

	if (error)

		goto out;

	/*

	 * If this is not a "fake" compatible device, then create the

	 * symlink from the class to the device.

	 */

	if (dev->kobj.parent != &dev->class->subsys.kobj) {

		error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,

					  dev->bus_id);

		if (error)

			goto out_subsys;

	}

	/* only bus-device parents get a "device"-link */

	if (dev->parent && dev->parent->bus) {

		error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,

					  "device");

		if (error)

			goto out_busid;

#ifdef CONFIG_SYSFS_DEPRECATED

		{

			char * class_name = make_class_name(dev->class->name,

								&dev->kobj);

			if (class_name)

				error = sysfs_create_link(&dev->parent->kobj,

							&dev->kobj, class_name);

			kfree(class_name);

			if (error)

				goto out_device;

		}

#endif

	}

	return 0;



#ifdef CONFIG_SYSFS_DEPRECATED

out_device:

	if (dev->parent)

		sysfs_remove_link(&dev->kobj, "device");

#endif

out_busid:

	if (dev->kobj.parent != &dev->class->subsys.kobj)

		sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id);

out_subsys:

	sysfs_remove_link(&dev->kobj, "subsystem");

out:

	return error;

}



static void device_remove_class_symlinks(struct device *dev)

{

	if (!dev->class)

		return;

	if (dev->parent) {

#ifdef CONFIG_SYSFS_DEPRECATED

		char *class_name;



		class_name = make_class_name(dev->class->name, &dev->kobj);

		if (class_name) {

			sysfs_remove_link(&dev->parent->kobj, class_name);

			kfree(class_name);

		}

#endif

		sysfs_remove_link(&dev->kobj, "device");

	}

	if (dev->kobj.parent != &dev->class->subsys.kobj)

		sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id);

	sysfs_remove_link(&dev->kobj, "subsystem");

}



/**

 *	device_add - add device to device hierarchy.

 *	@dev:	device.
@@ -674,7 +750,6 @@ static int setup_parent(struct device *dev, struct device *parent) 
int device_add(struct device *dev)

{

	struct device *parent = NULL;

	char *class_name = NULL;

	struct class_interface *class_intf;

	int error = -EINVAL;
@@ -714,27 +789,9 @@ int device_add(struct device *dev) 
			goto ueventattrError;

	}



	if (dev->class) {

		sysfs_create_link(&dev->kobj, &dev->class->subsys.kobj,

				  "subsystem");

		/* If this is not a "fake" compatible device, then create the

		 * symlink from the class to the device. */

		if (dev->kobj.parent != &dev->class->subsys.kobj)

			sysfs_create_link(&dev->class->subsys.kobj,

					  &dev->kobj, dev->bus_id);

		if (parent) {

			sysfs_create_link(&dev->kobj, &dev->parent->kobj,

							"device");

#ifdef CONFIG_SYSFS_DEPRECATED

			class_name = make_class_name(dev->class->name,

							&dev->kobj);

			if (class_name)

				sysfs_create_link(&dev->parent->kobj,

						  &dev->kobj, class_name);

#endif

		}

	}



	error = device_add_class_symlinks(dev);

	if (error)

		goto SymlinkError;

	error = device_add_attrs(dev);

	if (error)

		goto AttrsError;
@@ -761,7 +818,6 @@ int device_add(struct device *dev) 
		up(&dev->class->sem);

	}

 Done:

	kfree(class_name);

	put_device(dev);

	return error;

 BusError:
@@ -772,6 +828,8 @@ int device_add(struct device *dev) 
					     BUS_NOTIFY_DEL_DEVICE, dev);

	device_remove_attrs(dev);

 AttrsError:

	device_remove_class_symlinks(dev);

 SymlinkError:

	if (MAJOR(dev->devt))

		device_remove_file(dev, &devt_attr);
@@ -1156,7 +1214,7 @@ int device_rename(struct device *dev, char *new_name) 
{

	char *old_class_name = NULL;

	char *new_class_name = NULL;

	char *old_symlink_name = NULL;

	char *old_device_name = NULL;

	int error;



	dev = get_device(dev);
@@ -1170,42 +1228,49 @@ int device_rename(struct device *dev, char *new_name) 
		old_class_name = make_class_name(dev->class->name, &dev->kobj);

#endif



	if (dev->class) {

		old_symlink_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL);

		if (!old_symlink_name) {

	old_device_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL);

	if (!old_device_name) {

		error = -ENOMEM;

			goto out_free_old_class;

		}

		strlcpy(old_symlink_name, dev->bus_id, BUS_ID_SIZE);

		goto out;

	}



	strlcpy(old_device_name, dev->bus_id, BUS_ID_SIZE);

	strlcpy(dev->bus_id, new_name, BUS_ID_SIZE);



	error = kobject_rename(&dev->kobj, new_name);

	if (error) {

		strlcpy(dev->bus_id, old_device_name, BUS_ID_SIZE);

		goto out;

	}



#ifdef CONFIG_SYSFS_DEPRECATED

	if (old_class_name) {

		new_class_name = make_class_name(dev->class->name, &dev->kobj);

		if (new_class_name) {

			sysfs_create_link(&dev->parent->kobj, &dev->kobj,

					  new_class_name);

			error = sysfs_create_link(&dev->parent->kobj,

						  &dev->kobj, new_class_name);

			if (error)

				goto out;

			sysfs_remove_link(&dev->parent->kobj, old_class_name);

		}

	}

#endif



	if (dev->class) {

		sysfs_remove_link(&dev->class->subsys.kobj,

				  old_symlink_name);

		sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,

		sysfs_remove_link(&dev->class->subsys.kobj, old_device_name);

		error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,

					  dev->bus_id);

		if (error) {

			/* Uh... how to unravel this if restoring can fail? */

			dev_err(dev, "%s: sysfs_create_symlink failed (%d)\n",

				__FUNCTION__, error);

		}

	}

out:

	put_device(dev);



	kfree(new_class_name);

	kfree(old_symlink_name);

 out_free_old_class:

	kfree(old_class_name);

	kfree(old_device_name);



	return error;

}