Commit da231fd5 authored by Kay Sievers's avatar Kay Sievers Committed by Greg Kroah-Hartman
Browse files

Driver core: fix class glue dir cleanup logic 



We should remove the glue directory between the class and the bus
device _after_ we sent out the 'remove' event for the device, otherwise
the parent relationship is no longer valid, and composing the path
with deleted sysfs entries will not work.

Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent ef2c5174

drivers/base/core.c

+94 −112
Original line number Diff line number Diff line
@@ -18,7 +18,7 @@ 
#include <linux/string.h>

#include <linux/kdev_t.h>

#include <linux/notifier.h>



#include <linux/genhd.h>

#include <asm/semaphore.h>



#include "base.h"
@@ -541,19 +541,17 @@ void device_initialize(struct device *dev) 
static struct kobject *get_device_parent(struct device *dev,

					 struct device *parent)

{

	/*

	 * Set the parent to the class, not the parent device

	 * for topmost devices in class hierarchy.

	 * This keeps sysfs from having a symlink to make old

	 * udevs happy

	 */

	/* class devices without a parent live in /sys/class/<classname>/ */

	if (dev->class && (!parent || parent->class != dev->class))

		return &dev->class->subsys.kobj;

	/* all other devices keep their parent */

	else if (parent)

		return &parent->kobj;



	return NULL;

}



static inline void cleanup_device_parent(struct device *dev) {}

#else

static struct kobject *virtual_device_parent(struct device *dev)

{
@@ -618,6 +616,34 @@ static struct kobject * get_device_parent(struct device *dev, 
		return &parent->kobj;

	return NULL;

}



static void cleanup_device_parent(struct device *dev)

{

	struct device *d;

	int other = 0;



	if (!dev->class)

		return;



	/* see if we live in a parent class directory */

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

		return;



	/* if we are the last child of our class, delete the directory */

	down(&dev->class->sem);

	list_for_each_entry(d, &dev->class->devices, node) {

		if (d == dev)

			continue;

		if (d->kobj.parent == dev->kobj.parent) {

			other = 1;

			break;

		}

	}

	if (!other)

		kobject_del(dev->kobj.parent);

	kobject_put(dev->kobj.parent);

	up(&dev->class->sem);

}

#endif



static int setup_parent(struct device *dev, struct device *parent)
@@ -637,29 +663,28 @@ static int device_add_class_symlinks(struct device *dev) 


	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.

	 */



#ifdef CONFIG_SYSFS_DEPRECATED

	/* stacked class devices need a symlink in the class directory */

	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;

	}



	if (dev->parent) {

#ifdef CONFIG_SYSFS_DEPRECATED

		{

		struct device *parent = dev->parent;

		char *class_name;



		/*

			 * In old sysfs stacked class devices had 'device'

			 * link pointing to real device instead of parent

		 * stacked class devices have the 'device' link

		 * pointing to the bus device instead of the parent

		 */

		while (parent->class && !parent->bus && parent->parent)

			parent = parent->parent;
@@ -679,23 +704,33 @@ static int device_add_class_symlinks(struct device *dev) 
		if (error)

			goto out_device;

	}

	return 0;



out_device:

	if (dev->parent)

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

out_busid:

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

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

#else

	/* link in the class directory pointing to the device */

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

				  dev->bus_id);

	if (error)

		goto out_subsys;



	if (dev->parent) {

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

					  "device");

		if (error)

			goto out_busid;

#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);

#endif



out_subsys:

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

out:
@@ -706,8 +741,9 @@ static void device_remove_class_symlinks(struct device *dev) 
{

	if (!dev->class)

		return;

	if (dev->parent) {



#ifdef CONFIG_SYSFS_DEPRECATED

	if (dev->parent) {

		char *class_name;



		class_name = make_class_name(dev->class->name, &dev->kobj);
@@ -715,11 +751,18 @@ static void device_remove_class_symlinks(struct device *dev) 
			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);

#else

	if (dev->parent)

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



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

#endif



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

}
@@ -830,26 +873,6 @@ int device_add(struct device *dev) 
 SymlinkError:

	if (MAJOR(dev->devt))

		device_remove_file(dev, &devt_attr);



	if (dev->class) {

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

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

		 * symlink from the class to the device. */

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

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

					  dev->bus_id);

		if (parent) {

#ifdef CONFIG_SYSFS_DEPRECATED

			char *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");

		}

	}

 ueventattrError:

	device_remove_file(dev, &uevent_attr);

 attrError:
@@ -932,23 +955,7 @@ void device_del(struct device * dev) 
	if (MAJOR(dev->devt))

		device_remove_file(dev, &devt_attr);

	if (dev->class) {

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

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

		 * symlink from the class to the device. */

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

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

					  dev->bus_id);

		if (parent) {

#ifdef CONFIG_SYSFS_DEPRECATED

			char *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");

		}

		device_remove_class_symlinks(dev);



		down(&dev->class->sem);

		/* notify any interfaces that the device is now gone */
@@ -958,31 +965,6 @@ void device_del(struct device * dev) 
		/* remove the device from the class list */

		list_del_init(&dev->node);

		up(&dev->class->sem);



		/* If we live in a parent class-directory, unreference it */

		if (dev->kobj.parent->kset == &dev->class->class_dirs) {

			struct device *d;

			int other = 0;



			/*

			 * if we are the last child of our class, delete

			 * our class-directory at this parent

			 */

			down(&dev->class->sem);

			list_for_each_entry(d, &dev->class->devices, node) {

				if (d == dev)

					continue;

				if (d->kobj.parent == dev->kobj.parent) {

					other = 1;

					break;

				}

			}

			if (!other)

				kobject_del(dev->kobj.parent);



			kobject_put(dev->kobj.parent);

			up(&dev->class->sem);

		}

	}

	device_remove_file(dev, &uevent_attr);

	device_remove_attrs(dev);
@@ -1004,8 +986,8 @@ void device_del(struct device * dev) 
		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,

					     BUS_NOTIFY_DEL_DEVICE, dev);

	kobject_uevent(&dev->kobj, KOBJ_REMOVE);

	cleanup_device_parent(dev);

	kobject_del(&dev->kobj);

	if (parent)

	put_device(parent);

}

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