NTFS: - Fix bug in fs/ntfs/attrib.c::ntfs_find_vcn_nolock() where after

dropping the read lock and taking the write lock we were not checking
        whether someone else did not already do the work we wanted to do.
      - Rename ntfs_find_vcn_nolock() to ntfs_attr_find_vcn_nolock().
      - Tidy up some comments in fs/ntfs/runlist.c.
      - Add LCN_ENOMEM and LCN_EIO definitions to fs/ntfs/runlist.h.

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>

fs/ntfs/runlist.h

@@ -66,6 +66,8 @@ typedef enum {
 	LCN_HOLE		= -1,	/* Keep this as highest value or die! */
 	LCN_RL_NOT_MAPPED	= -2,
 	LCN_ENOENT		= -3,
+	LCN_ENOMEM		= -4,
+	LCN_EIO			= -5,
 } LCN_SPECIAL_VALUES;
 
 extern runlist_element *ntfs_runlists_merge(runlist_element *drl,