vfs: clear to the end of the buffer on partial buffer reads

Dan Carpenter · torvalds · commit 27d7c2a006a8 · 2012-12-05T10:32:59.000-08:00
READ is zero so the "rw &amp; READ" test is always false.  The intended test
was "((rw &amp; RW_MASK) == READ)".

Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
diff --git a/fs/buffer.c b/fs/buffer.c
@@ -2935,7 +2935,7 @@ static void guard_bh_eod(int rw, struct bio *bio, struct buffer_head *bh)
 	bio->bi_io_vec[0].bv_len = bytes;
 
 	/* ..and clear the end of the buffer for reads */
-	if (rw & READ) {
+	if ((rw & RW_MASK) == READ) {
 		void *kaddr = kmap_atomic(bh->b_page);
 		memset(kaddr + bh_offset(bh) + bytes, 0, bh->b_size - bytes);
 		kunmap_atomic(kaddr);
