udf: use get_bh()

Make UDF use get_bh() instead of directly accessing b_count and use
brelse() instead of udf_release_data() which does just brelse()...

Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/udf/symlink.c b/fs/udf/symlink.c
index ba068a7..12613b6 100644
--- a/fs/udf/symlink.c
+++ b/fs/udf/symlink.c
@@ -95,7 +95,7 @@
 	}
 
 	udf_pc_to_char(inode->i_sb, symlink, inode->i_size, p);
-	udf_release_data(bh);
+	brelse(bh);
 
 	unlock_kernel();
 	SetPageUptodate(page);