[PATCH 4/6] UDF cleanup and fixes

[Jan Kara <jack@suse.cz>]

Add a few assertions into udf_discard_prealloc() to check that the file
is sane (mostly helps debugging further patches ;).

Signed-off-by: Jan Kara <jack@suse.cz>

diff -rupX /home/jack/.kerndiffexclude linux-2.6.20-3-udf_buffer_handling/fs/udf/truncate.c linux-2.6.20-4-udf_discard_prealloc_cleanup/fs/udf/truncate.c
--- linux-2.6.20-3-udf_buffer_handling/fs/udf/truncate.c	2007-03-06 15:02:33.000000000 +0100
+++ linux-2.6.20-4-udf_discard_prealloc_cleanup/fs/udf/truncate.c	2007-03-06 15:03:00.000000000 +0100
@@ -88,8 +88,9 @@ void udf_discard_prealloc(struct inode *
 	{
 		etype = netype;
 		lbcount += elen;
-		if (lbcount > inode->i_size && lbcount - inode->i_size < inode->i_sb->s_blocksize)
+		if (lbcount > inode->i_size && lbcount - elen < inode->i_size)
 		{
+			WARN_ON(lbcount - inode->i_size >= inode->i_sb->s_blocksize);
 			nelen = elen - (lbcount - inode->i_size);
 			epos.offset -= adsize;
 			extent_trunc(inode, &epos, eloc, etype, elen, nelen);
@@ -119,6 +120,7 @@ void udf_discard_prealloc(struct inode *
 	}
 	UDF_I_LENEXTENTS(inode) = lbcount;
 
+	WARN_ON(lbcount != inode->i_size);
 	brelse(epos.bh);
 }