Merge tag 'driver-core-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and sysfs updates from Greg KH:
 "Here's the big driver core / sysfs update for 3.15-rc1.

  Lots of kernfs updates to make it useful for other subsystems, and a
  few other tiny driver core patches.

  All have been in linux-next for a while"

* tag 'driver-core-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (42 commits)
  Revert "sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()"
  kernfs: cache atomic_write_len in kernfs_open_file
  numa: fix NULL pointer access and memory leak in unregister_one_node()
  Revert "driver core: synchronize device shutdown"
  kernfs: fix off by one error.
  kernfs: remove duplicate dir.c at the top dir
  x86: align x86 arch with generic CPU modalias handling
  cpu: add generic support for CPU feature based module autoloading
  sysfs: create bin_attributes under the requested group
  driver core: unexport static function create_syslog_header
  firmware: use power efficient workqueue for unloading and aborting fw load
  firmware: give a protection when map page failed
  firmware: google memconsole driver fixes
  firmware: fix google/gsmi duplicate efivars_sysfs_init()
  drivers/base: delete non-required instances of include <linux/init.h>
  kernfs: fix kernfs_node_from_dentry()
  ACPI / platform: drop redundant ACPI_HANDLE check
  kernfs: fix hash calculation in kernfs_rename_ns()
  kernfs: add CONFIG_KERNFS
  sysfs, kobject: add sysfs wrapper for kernfs_enable_ns()
  ...

2 files changed, 23 insertions, 17 deletions

diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index ebf41e228e55..ee0e85abe1fd 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -304,12 +304,6 @@ dcssblk_load_segment(char *name, struct segment_info **seg_info)
         return rc;
 }
 
-static void dcssblk_unregister_callback(struct device *dev)
-{
-        device_unregister(dev);
-        put_device(dev);
-}
-
 /*
  * device attribute for switching shared/nonshared (exclusive)
  * operation (show + store)
@@ -397,7 +391,13 @@ removeseg:
         blk_cleanup_queue(dev_info->dcssblk_queue);
         dev_info->gd->queue = NULL;
         put_disk(dev_info->gd);
-        rc = device_schedule_callback(dev, dcssblk_unregister_callback);
+        up_write(&dcssblk_devices_sem);
+
+        if (device_remove_file_self(dev, attr)) {
+                device_unregister(dev);
+                put_device(dev);
+        }
+        return rc;
 out:
         up_write(&dcssblk_devices_sem);
         return rc;
diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index fd3367a1dc7a..dfd7bc681c25 100644
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -168,14 +168,12 @@ static ssize_t ccwgroup_online_show(struct device *dev,
  * 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)
+static void ccwgroup_ungroup(struct ccwgroup_device *gdev)
 {
-        struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
-
         mutex_lock(&gdev->reg_mutex);
         if (device_is_registered(&gdev->dev)) {
                 __ccwgroup_remove_symlinks(gdev);
-                device_unregister(dev);
+                device_unregister(&gdev->dev);
                 __ccwgroup_remove_cdev_refs(gdev);
         }
         mutex_unlock(&gdev->reg_mutex);
@@ -195,10 +193,9 @@ static ssize_t ccwgroup_ungroup_store(struct device *dev,
                 rc = -EINVAL;
                 goto out;
         }
-        /* 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 (device_remove_file_self(dev, attr))
+                ccwgroup_ungroup(gdev);
 out:
         if (rc) {
                 if (rc != -EAGAIN)
@@ -224,6 +221,14 @@ static const struct attribute_group *ccwgroup_attr_groups[] = {
         NULL,
 };
 
+static void ccwgroup_ungroup_workfn(struct work_struct *work)
+{
+        struct ccwgroup_device *gdev =
+                container_of(work, struct ccwgroup_device, ungroup_work);
+
+        ccwgroup_ungroup(gdev);
+}
+
 static void ccwgroup_release(struct device *dev)
 {
         kfree(to_ccwgroupdev(dev));
@@ -323,6 +328,7 @@ int ccwgroup_create_dev(struct device *parent, struct ccwgroup_driver *gdrv,
         atomic_set(&gdev->onoff, 0);
         mutex_init(&gdev->reg_mutex);
         mutex_lock(&gdev->reg_mutex);
+        INIT_WORK(&gdev->ungroup_work, ccwgroup_ungroup_workfn);
         gdev->count = num_devices;
         gdev->dev.bus = &ccwgroup_bus_type;
         gdev->dev.parent = parent;
@@ -404,10 +410,10 @@ EXPORT_SYMBOL(ccwgroup_create_dev);
 static int ccwgroup_notifier(struct notifier_block *nb, unsigned long action,
                              void *data)
 {
-        struct device *dev = data;
+        struct ccwgroup_device *gdev = to_ccwgroupdev(data);
 
         if (action == BUS_NOTIFY_UNBIND_DRIVER)
-                device_schedule_callback(dev, ccwgroup_ungroup_callback);
+                schedule_work(&gdev->ungroup_work);
 
         return NOTIFY_OK;
 }