1 files changed, 49 insertions, 33 deletions

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 6bee6af8d8e1..b56a0ba31d4a 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -56,7 +56,14 @@ static inline int device_is_not_partition(struct device *dev)
  */
 const char *dev_driver_string(const struct device *dev)
 {
-        return dev->driver ? dev->driver->name :
+        struct device_driver *drv;
+
+        /* dev->driver can change to NULL underneath us because of unbinding,
+         * so be careful about accessing it.  dev->bus and dev->class should
+         * never change once they are set, so they don't need special care.
+         */
+        drv = ACCESS_ONCE(dev->driver);
+        return drv ? drv->name :
                         (dev->bus ? dev->bus->name :
                         (dev->class ? dev->class->name : ""));
 }
@@ -93,7 +100,7 @@ static ssize_t dev_attr_store(struct kobject *kobj, struct attribute *attr,
         return ret;
 }
 
-static struct sysfs_ops dev_sysfs_ops = {
+static const struct sysfs_ops dev_sysfs_ops = {
         .show   = dev_attr_show,
         .store  = dev_attr_store,
 };
@@ -245,7 +252,7 @@ static int dev_uevent(struct kset *kset, struct kobject *kobj,
         return retval;
 }
 
-static struct kset_uevent_ops device_uevent_ops = {
+static const struct kset_uevent_ops device_uevent_ops = {
         .filter =       dev_uevent_filter,
         .name =         dev_uevent_name,
         .uevent =       dev_uevent,
@@ -299,15 +306,10 @@ static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
 {
         enum kobject_action action;
 
-        if (kobject_action_type(buf, count, &action) == 0) {
+        if (kobject_action_type(buf, count, &action) == 0)
                 kobject_uevent(&dev->kobj, action);
-                goto out;
-        }
-
-        dev_err(dev, "uevent: unsupported action-string; this will "
-                     "be ignored in a future kernel version\n");
-        kobject_uevent(&dev->kobj, KOBJ_ADD);
-out:
+        else
+                dev_err(dev, "uevent: unknown action-string\n");
         return count;
 }
 
@@ -439,7 +441,8 @@ struct kset *devices_kset;
  * @dev: device.
  * @attr: device attribute descriptor.
  */
-int device_create_file(struct device *dev, struct device_attribute *attr)
+int device_create_file(struct device *dev,
+                       const struct device_attribute *attr)
 {
         int error = 0;
         if (dev)
@@ -452,7 +455,8 @@ int device_create_file(struct device *dev, struct device_attribute *attr)
  * @dev: device.
  * @attr: device attribute descriptor.
  */
-void device_remove_file(struct device *dev, struct device_attribute *attr)
+void device_remove_file(struct device *dev,
+                        const struct device_attribute *attr)
 {
         if (dev)
                 sysfs_remove_file(&dev->kobj, &attr->attr);
@@ -463,7 +467,8 @@ void device_remove_file(struct device *dev, struct device_attribute *attr)
  * @dev: device.
  * @attr: device binary attribute descriptor.
  */
-int device_create_bin_file(struct device *dev, struct bin_attribute *attr)
+int device_create_bin_file(struct device *dev,
+                           const struct bin_attribute *attr)
 {
         int error = -EINVAL;
         if (dev)
@@ -477,7 +482,8 @@ EXPORT_SYMBOL_GPL(device_create_bin_file);
  * @dev: device.
  * @attr: device binary attribute descriptor.
  */
-void device_remove_bin_file(struct device *dev, struct bin_attribute *attr)
+void device_remove_bin_file(struct device *dev,
+                            const struct bin_attribute *attr)
 {
         if (dev)
                 sysfs_remove_bin_file(&dev->kobj, attr);
@@ -596,6 +602,7 @@ static struct kobject *get_device_parent(struct device *dev,
         int retval;
 
         if (dev->class) {
+                static DEFINE_MUTEX(gdp_mutex);
                 struct kobject *kobj = NULL;
                 struct kobject *parent_kobj;
                 struct kobject *k;
@@ -612,6 +619,8 @@ static struct kobject *get_device_parent(struct device *dev,
                 else
                         parent_kobj = &parent->kobj;
 
+                mutex_lock(&gdp_mutex);
+
                 /* find our class-directory at the parent and reference it */
                 spin_lock(&dev->class->p->class_dirs.list_lock);
                 list_for_each_entry(k, &dev->class->p->class_dirs.list, entry)
@@ -620,20 +629,26 @@ static struct kobject *get_device_parent(struct device *dev,
                                 break;
                         }
                 spin_unlock(&dev->class->p->class_dirs.list_lock);
-                if (kobj)
+                if (kobj) {
+                        mutex_unlock(&gdp_mutex);
                         return kobj;
+                }
 
                 /* or create a new class-directory at the parent device */
                 k = kobject_create();
-                if (!k)
+                if (!k) {
+                        mutex_unlock(&gdp_mutex);
                         return NULL;
+                }
                 k->kset = &dev->class->p->class_dirs;
                 retval = kobject_add(k, parent_kobj, "%s", dev->class->name);
                 if (retval < 0) {
+                        mutex_unlock(&gdp_mutex);
                         kobject_put(k);
                         return NULL;
                 }
                 /* do not emit an uevent for this simple "glue" directory */
+                mutex_unlock(&gdp_mutex);
                 return k;
         }
 
@@ -898,8 +913,10 @@ int device_add(struct device *dev)
                 dev->init_name = NULL;
         }
 
-        if (!dev_name(dev))
+        if (!dev_name(dev)) {
+                error = -EINVAL;
                 goto name_error;
+        }
 
         pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
 
@@ -987,6 +1004,8 @@ done:
         device_remove_class_symlinks(dev);
  SymlinkError:
         if (MAJOR(dev->devt))
+                devtmpfs_delete_node(dev);
+        if (MAJOR(dev->devt))
                 device_remove_sys_dev_entry(dev);
  devtattrError:
         if (MAJOR(dev->devt))
@@ -1326,6 +1345,8 @@ static void root_device_release(struct device *dev)
  * 'module' symlink which points to the @owner directory
  * in sysfs.
  *
+ * Returns &struct device pointer on success, or ERR_PTR() on error.
+ *
  * Note: You probably want to use root_device_register().
  */
 struct device *__root_device_register(const char *name, struct module *owner)
@@ -1413,6 +1434,8 @@ static void device_create_release(struct device *dev)
  * Any further sysfs files that might be required can be created using this
  * pointer.
  *
+ * Returns &struct device pointer on success, or ERR_PTR() on error.
+ *
  * Note: the struct class passed to this function must have previously
  * been created with a call to class_create().
  */
@@ -1473,6 +1496,8 @@ EXPORT_SYMBOL_GPL(device_create_vargs);
  * Any further sysfs files that might be required can be created using this
  * pointer.
  *
+ * Returns &struct device pointer on success, or ERR_PTR() on error.
+ *
  * Note: the struct class passed to this function must have previously
  * been created with a call to class_create().
  */
@@ -1559,22 +1584,16 @@ int device_rename(struct device *dev, char *new_name)
         if (old_class_name) {
                 new_class_name = make_class_name(dev->class->name, &dev->kobj);
                 if (new_class_name) {
-                        error = sysfs_create_link_nowarn(&dev->parent->kobj,
-                                                         &dev->kobj,
-                                                         new_class_name);
-                        if (error)
-                                goto out;
-                        sysfs_remove_link(&dev->parent->kobj, old_class_name);
+                        error = sysfs_rename_link(&dev->parent->kobj,
+                                                  &dev->kobj,
+                                                  old_class_name,
+                                                  new_class_name);
                 }
         }
 #else
         if (dev->class) {
-                error = sysfs_create_link_nowarn(&dev->class->p->class_subsys.kobj,
-                                                 &dev->kobj, dev_name(dev));
-                if (error)
-                        goto out;
-                sysfs_remove_link(&dev->class->p->class_subsys.kobj,
-                                  old_device_name);
+                error = sysfs_rename_link(&dev->class->p->class_subsys.kobj,
+                                          &dev->kobj, old_device_name, new_name);
         }
 #endif
 
@@ -1728,8 +1747,5 @@ void device_shutdown(void)
                         dev->driver->shutdown(dev);
                 }
         }
-        kobject_put(sysfs_dev_char_kobj);
-        kobject_put(sysfs_dev_block_kobj);
-        kobject_put(dev_kobj);
         async_synchronize_full();
 }