CHROMIUM: add boot-to-device mapper support.

include/linux/device-mapper.h

 /*
  * Copyright (C) 2001 Sistina Software (UK) Limited.
  * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
  *
  * This file is released under the LGPL.
  */
 
 #ifndef _LINUX_DEVICE_MAPPER_H
 #define _LINUX_DEVICE_MAPPER_H
 
@@ skipping 198 matching lines @@
 void dm_get(struct mapped_device *md);
 void dm_put(struct mapped_device *md);
 
 /*
  * An arbitrary pointer may be stored alongside a mapped device.
  */
 void dm_set_mdptr(struct mapped_device *md, void *ptr);
 void *dm_get_mdptr(struct mapped_device *md);
 
 /*
+ * Export the device via the ioctl interface (uses mdptr).
+ */
+int dm_ioctl_export(struct mapped_device *md, const char *name,
+                    const char *uuid);
+
+/*
  * A device can still be used while suspended, but I/O is deferred.
  */
 int dm_suspend(struct mapped_device *md, unsigned suspend_flags);
 int dm_resume(struct mapped_device *md);
 
 /*
  * Event functions.
  */
 uint32_t dm_get_event_nr(struct mapped_device *md);
 int dm_wait_event(struct mapped_device *md, int event_nr);
@@ skipping 174 matching lines @@
 
 /*-----------------------------------------------------------------
  * Helper for block layer and dm core operations
  *---------------------------------------------------------------*/
 void dm_dispatch_request(struct request *rq);
 void dm_requeue_unmapped_request(struct request *rq);
 void dm_kill_unmapped_request(struct request *rq, int error);
 int dm_underlying_device_busy(struct request_queue *q);
 
 #endif  /* _LINUX_DEVICE_MAPPER_H */