XArray: Honour reserved entries in xa_insert

xa_insert() should treat reserved entries as occupied, not as available.
Also, it should treat requests to insert a NULL pointer as a request
to reserve the slot.  Add xa_insert_bh() and xa_insert_irq() for
completeness.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

1 files changed, 5 insertions, 3 deletions

diff --git a/lib/test_xarray.c b/lib/test_xarray.c
index 6e0212a60b08..3cf17338b0a4 100644
--- a/lib/test_xarray.c
+++ b/lib/test_xarray.c
@@ -382,10 +382,12 @@ static noinline void check_reserve(struct xarray *xa)
         xa_erase_index(xa, 12345678);
         XA_BUG_ON(xa, !xa_empty(xa));
 
-        /* And so does xa_insert */
+        /* But xa_insert does not */
         xa_reserve(xa, 12345678, GFP_KERNEL);
-        XA_BUG_ON(xa, xa_insert(xa, 12345678, xa_mk_value(12345678), 0) != 0);
-        xa_erase_index(xa, 12345678);
+        XA_BUG_ON(xa, xa_insert(xa, 12345678, xa_mk_value(12345678), 0) !=
+                        -EEXIST);
+        XA_BUG_ON(xa, xa_empty(xa));
+        XA_BUG_ON(xa, xa_erase(xa, 12345678) != NULL);
         XA_BUG_ON(xa, !xa_empty(xa));
 
         /* Can iterate through a reserved entry */