On-disk format definition for huge files

- EXT4_FEATURE_RO_COMPAT_HUGE_FILE (0x0008) - change i_blocks to be
  in units of s_blocksize units instead of 512-byte sectors, use
  l_i_frag and l_i_fsize as i_blocks_hi (could also be part of 64BIT).

E2fsck and debugfs changed to support i_blocks_hi instead of l_i_frag and
l_i_fsize.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/e2fsck/problem.c b/e2fsck/problem.c
index 2dc3073..7f6add4 100644
--- a/e2fsck/problem.c
+++ b/e2fsck/problem.c
@@ -1173,6 +1173,11 @@
 	  N_("Duplicate @e '%Dn' found.\n\tMarking %p (%i) to be rebuilt.\n\n"),
 	  PROMPT_NONE, 0 },
 	
+  	/* i_blocks_hi should be zero */
+	{ PR_2_BLOCKS_HI_ZERO,
+	  N_("i_blocks_hi @F %N, @s zero.\n"),
+	  PROMPT_CLEAR, 0 },
+
 	/* Pass 3 errors */
 
 	/* Pass 3: Checking directory connectivity */