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the parent relationship is no longer valid, and composing the path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: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 22fdf320a2a68756ffee456ba9531dec7e5d79d2..13cae18936c5c467b949e30b8eb7e852e10a9fdf 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -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"
@@ -538,22 +538,20 @@ void device_initialize(struct device *dev)
 }
 
 #ifdef CONFIG_SYSFS_DEPRECATED
-static struct kobject * get_device_parent(struct device *dev,
-                                         struct device *parent)
+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)
 {
@@ -566,8 +564,8 @@ static struct kobject *virtual_device_parent(struct device *dev)
        return virtual_dir;
 }
 
-static struct kobject * get_device_parent(struct device *dev,
-                                         struct device *parent)
+static struct kobject *get_device_parent(struct device *dev,
+                                        struct device *parent)
 {
        int retval;
 
@@ -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)
@@ -637,65 +663,74 @@ 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
-                        */
-                       while (parent->class && !parent->bus && parent->parent)
-                               parent = parent->parent;
-
-                       error = sysfs_create_link(&dev->kobj,
-                                                 &parent->kobj,
-                                                 "device");
-                       if (error)
-                               goto out_busid;
+               struct device *parent = dev->parent;
+               char *class_name;
 
-                       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;
-               }
-#else
-               error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
+               /*
+                * 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;
+
+               error = sysfs_create_link(&dev->kobj,
+                                         &parent->kobj,
                                          "device");
                if (error)
                        goto out_busid;
-#endif
+
+               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;
        }
        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);
+#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;
+       }
+       return 0;
+
+out_busid:
+       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);
@@ -1004,9 +986,9 @@ 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);
+       put_device(parent);
 }
 
 /**