NTFS: - Add disable_sparse mount option together with a per volume sparse

enable bit which is set appropriately and a per inode sparse disable
	bit which is preset on some system file inodes as appropriate.
      - Enforce that sparse support is disabled on NTFS volumes pre 3.0.

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

fs/ntfs/inode.h

@@ -2,7 +2,7 @@
  * inode.h - Defines for inode structures NTFS Linux kernel driver. Part of
  *	     the Linux-NTFS project.
  *
- * Copyright (c) 2001-2004 Anton Altaparmakov
+ * Copyright (c) 2001-2005 Anton Altaparmakov
  * Copyright (c) 2002 Richard Russon
  *
  * This program/include file is free software; you can redistribute it and/or
@@ -166,6 +166,7 @@ typedef enum {
 	NI_Sparse,		/* 1: Unnamed data attr is sparse (f).
 				   1: Create sparse files by default (d).
 				   1: Attribute is sparse (a). */
+	NI_SparseDisabled,	/* 1: May not create sparse regions. */
 	NI_TruncateFailed,	/* 1: Last ntfs_truncate() call failed. */
 } ntfs_inode_state_bits;
 
@@ -218,6 +219,7 @@ NINO_FNS(IndexAllocPresent)
 NINO_FNS(Compressed)
 NINO_FNS(Encrypted)
 NINO_FNS(Sparse)
+NINO_FNS(SparseDisabled)
 NINO_FNS(TruncateFailed)
 
 /*