XArray: Test two more things about xa_cmpxchg
1. If we xa_cmpxchg() an entry in, it marks the index as not free.
2. If we xa_cmpxchg() NULL in, it marks the index as free.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
diff --git a/lib/test_xarray.c b/lib/test_xarray.c
index d4f9792..9fc3da4 100644
--- a/lib/test_xarray.c
+++ b/lib/test_xarray.c
@@ -393,6 +393,9 @@ static noinline void check_cmpxchg(struct xarray *xa)
XA_BUG_ON(xa, xa_cmpxchg(xa, 12345678, FIVE, LOTS, GFP_KERNEL) != FIVE);
XA_BUG_ON(xa, xa_cmpxchg(xa, 5, FIVE, NULL, GFP_KERNEL) != NULL);
XA_BUG_ON(xa, xa_cmpxchg(xa, 5, NULL, FIVE, GFP_KERNEL) != NULL);
+ XA_BUG_ON(xa, xa_insert(xa, 5, FIVE, GFP_KERNEL) != -EBUSY);
+ XA_BUG_ON(xa, xa_cmpxchg(xa, 5, FIVE, NULL, GFP_KERNEL) != FIVE);
+ XA_BUG_ON(xa, xa_insert(xa, 5, FIVE, GFP_KERNEL) == -EBUSY);
xa_erase_index(xa, 12345678);
xa_erase_index(xa, 5);
XA_BUG_ON(xa, !xa_empty(xa));