dm sysfs: fix a module unload race

[linux-2.6-block.git] / drivers / md / dm.h

diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 1ab2028559caaa7416cee11f532e7282bf8b3c4f..c4569f02f50f1a181ed6f6f2bd797bd62c0c7f47 100644 (file)
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -16,6 +16,7 @@
 #include <linux/blkdev.h>
 #include <linux/hdreg.h>
 #include <linux/completion.h>
+#include <linux/kobject.h>
 
 #include "dm-stats.h"
 
@@ -149,11 +150,25 @@ void dm_interface_exit(void);
 /*
  * sysfs interface
  */
+struct dm_kobject_holder {
+       struct kobject kobj;
+       struct completion completion;
+};
+
+static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
+{
+       return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;
+}
+
 int dm_sysfs_init(struct mapped_device *md);
 void dm_sysfs_exit(struct mapped_device *md);
 struct kobject *dm_kobject(struct mapped_device *md);
 struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
-struct completion *dm_get_completion_from_kobject(struct kobject *kobj);
+
+/*
+ * The kobject helper
+ */
+void dm_kobject_release(struct kobject *kobj);
 
 /*
  * Targets for linear and striped mappings