Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 2278 insertions, 0 deletions

diff --git a/lib/test_xarray.c b/lib/test_xarray.c
new file mode 100644
index 000000000..5ca0aefee
--- /dev/null
+++ b/lib/test_xarray.c
@@ -0,0 +1,2278 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * test_xarray.c: Test the XArray API
+ * Copyright (c) 2017-2018 Microsoft Corporation
+ * Copyright (c) 2019-2020 Oracle
+ * Author: Matthew Wilcox <willy@infradead.org>
+ */
+
+#include <linux/xarray.h>
+#include <linux/module.h>
+
+static unsigned int tests_run;
+static unsigned int tests_passed;
+
+static const unsigned int order_limit =
+		IS_ENABLED(CONFIG_XARRAY_MULTI) ? BITS_PER_LONG : 1;
+
+#ifndef XA_DEBUG
+# ifdef __KERNEL__
+void xa_dump(const struct xarray *xa) { }
+# endif
+#undef XA_BUG_ON
+#define XA_BUG_ON(xa, x) do {					\
+	tests_run++;						\
+	if (x) {						\
+		printk("BUG at %s:%d\n", __func__, __LINE__);	\
+		xa_dump(xa);					\
+		dump_stack();					\
+	} else {						\
+		tests_passed++;					\
+	}							\
+} while (0)
+#endif
+
+static void *xa_mk_index(unsigned long index)
+{
+	return xa_mk_value(index & LONG_MAX);
+}
+
+static void *xa_store_index(struct xarray *xa, unsigned long index, gfp_t gfp)
+{
+	return xa_store(xa, index, xa_mk_index(index), gfp);
+}
+
+static void xa_insert_index(struct xarray *xa, unsigned long index)
+{
+	XA_BUG_ON(xa, xa_insert(xa, index, xa_mk_index(index),
+				GFP_KERNEL) != 0);
+}
+
+static void xa_alloc_index(struct xarray *xa, unsigned long index, gfp_t gfp)
+{
+	u32 id;
+
+	XA_BUG_ON(xa, xa_alloc(xa, &id, xa_mk_index(index), xa_limit_32b,
+				gfp) != 0);
+	XA_BUG_ON(xa, id != index);
+}
+
+static void xa_erase_index(struct xarray *xa, unsigned long index)
+{
+	XA_BUG_ON(xa, xa_erase(xa, index) != xa_mk_index(index));
+	XA_BUG_ON(xa, xa_load(xa, index) != NULL);
+}
+
+/*
+ * If anyone needs this, please move it to xarray.c.  We have no current
+ * users outside the test suite because all current multislot users want
+ * to use the advanced API.
+ */
+static void *xa_store_order(struct xarray *xa, unsigned long index,
+		unsigned order, void *entry, gfp_t gfp)
+{
+	XA_STATE_ORDER(xas, xa, index, order);
+	void *curr;
+
+	do {
+		xas_lock(&xas);
+		curr = xas_store(&xas, entry);
+		xas_unlock(&xas);
+	} while (xas_nomem(&xas, gfp));
+
+	return curr;
+}
+
+static noinline void check_xa_err(struct xarray *xa)
+{
+	XA_BUG_ON(xa, xa_err(xa_store_index(xa, 0, GFP_NOWAIT)) != 0);
+	XA_BUG_ON(xa, xa_err(xa_erase(xa, 0)) != 0);
+#ifndef __KERNEL__
+	/* The kernel does not fail GFP_NOWAIT allocations */
+	XA_BUG_ON(xa, xa_err(xa_store_index(xa, 1, GFP_NOWAIT)) != -ENOMEM);
+	XA_BUG_ON(xa, xa_err(xa_store_index(xa, 1, GFP_NOWAIT)) != -ENOMEM);
+#endif
+	XA_BUG_ON(xa, xa_err(xa_store_index(xa, 1, GFP_KERNEL)) != 0);
+	XA_BUG_ON(xa, xa_err(xa_store(xa, 1, xa_mk_value(0), GFP_KERNEL)) != 0);
+	XA_BUG_ON(xa, xa_err(xa_erase(xa, 1)) != 0);
+// kills the test-suite :-(
+//	XA_BUG_ON(xa, xa_err(xa_store(xa, 0, xa_mk_internal(0), 0)) != -EINVAL);
+}
+
+static noinline void check_xas_retry(struct xarray *xa)
+{
+	XA_STATE(xas, xa, 0);
+	void *entry;
+
+	xa_store_index(xa, 0, GFP_KERNEL);
+	xa_store_index(xa, 1, GFP_KERNEL);
+
+	rcu_read_lock();
+	XA_BUG_ON(xa, xas_find(&xas, ULONG_MAX) != xa_mk_value(0));
+	xa_erase_index(xa, 1);
+	XA_BUG_ON(xa, !xa_is_retry(xas_reload(&xas)));
+	XA_BUG_ON(xa, xas_retry(&xas, NULL));
+	XA_BUG_ON(xa, xas_retry(&xas, xa_mk_value(0)));
+	xas_reset(&xas);
+	XA_BUG_ON(xa, xas.xa_node != XAS_RESTART);
+	XA_BUG_ON(xa, xas_next_entry(&xas, ULONG_MAX) != xa_mk_value(0));
+	XA_BUG_ON(xa, xas.xa_node != NULL);
+	rcu_read_unlock();
+
+	XA_BUG_ON(xa, xa_store_index(xa, 1, GFP_KERNEL) != NULL);
+
+	rcu_read_lock();
+	XA_BUG_ON(xa, !xa_is_internal(xas_reload(&xas)));
+	xas.xa_node = XAS_RESTART;
+	XA_BUG_ON(xa, xas_next_entry(&xas, ULONG_MAX) != xa_mk_value(0));
+	rcu_read_unlock();
+
+	/* Make sure we can iterate through retry entries */
+	xas_lock(&xas);
+	xas_set(&xas, 0);
+	xas_store(&xas, XA_RETRY_ENTRY);
+	xas_set(&xas, 1);
+	xas_store(&xas, XA_RETRY_ENTRY);
+
+	xas_set(&xas, 0);
+	xas_for_each(&xas, entry, ULONG_MAX) {
+		xas_store(&xas, xa_mk_index(xas.xa_index));
+	}
+	xas_unlock(&xas);
+
+	xa_erase_index(xa, 0);
+	xa_erase_index(xa, 1);
+}
+
+static noinline void check_xa_load(struct xarray *xa)
+{
+	unsigned long i, j;
+
+	for (i = 0; i < 1024; i++) {
+		for (j = 0; j < 1024; j++) {
+			void *entry = xa_load(xa, j);
+			if (j < i)
+				XA_BUG_ON(xa, xa_to_value(entry) != j);
+			else
+				XA_BUG_ON(xa, entry);
+		}
+		XA_BUG_ON(xa, xa_store_index(xa, i, GFP_KERNEL) != NULL);
+	}
+
+	for (i = 0; i < 1024; i++) {
+		for (j = 0; j < 1024; j++) {
+			void *entry = xa_load(xa, j);
+			if (j >= i)
+				XA_BUG_ON(xa, xa_to_value(entry) != j);
+			else
+				XA_BUG_ON(xa, entry);
+		}
+		xa_erase_index(xa, i);
+	}
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_xa_mark_1(struct xarray *xa, unsigned long index)
+{
+	unsigned int order;
+	unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 8 : 1;
+
+	/* NULL elements have no marks set */
+	XA_BUG_ON(xa, xa_get_mark(xa, index, XA_MARK_0));
+	xa_set_mark(xa, index, XA_MARK_0);
+	XA_BUG_ON(xa, xa_get_mark(xa, index, XA_MARK_0));
+
+	/* Storing a pointer will not make a mark appear */
+	XA_BUG_ON(xa, xa_store_index(xa, index, GFP_KERNEL) != NULL);
+	XA_BUG_ON(xa, xa_get_mark(xa, index, XA_MARK_0));
+	xa_set_mark(xa, index, XA_MARK_0);
+	XA_BUG_ON(xa, !xa_get_mark(xa, index, XA_MARK_0));
+
+	/* Setting one mark will not set another mark */
+	XA_BUG_ON(xa, xa_get_mark(xa, index + 1, XA_MARK_0));
+	XA_BUG_ON(xa, xa_get_mark(xa, index, XA_MARK_1));
+
+	/* Storing NULL clears marks, and they can't be set again */
+	xa_erase_index(xa, index);
+	XA_BUG_ON(xa, !xa_empty(xa));
+	XA_BUG_ON(xa, xa_get_mark(xa, index, XA_MARK_0));
+	xa_set_mark(xa, index, XA_MARK_0);
+	XA_BUG_ON(xa, xa_get_mark(xa, index, XA_MARK_0));
+
+	/*
+	 * Storing a multi-index entry over entries with marks gives the
+	 * entire entry the union of the marks
+	 */
+	BUG_ON((index % 4) != 0);
+	for (order = 2; order < max_order; order++) {
+		unsigned long base = round_down(index, 1UL << order);
+		unsigned long next = base + (1UL << order);
+		unsigned long i;
+
+		XA_BUG_ON(xa, xa_store_index(xa, index + 1, GFP_KERNEL));
+		xa_set_mark(xa, index + 1, XA_MARK_0);
+		XA_BUG_ON(xa, xa_store_index(xa, index + 2, GFP_KERNEL));
+		xa_set_mark(xa, index + 2, XA_MARK_2);
+		XA_BUG_ON(xa, xa_store_index(xa, next, GFP_KERNEL));
+		xa_store_order(xa, index, order, xa_mk_index(index),
+				GFP_KERNEL);
+		for (i = base; i < next; i++) {
+			XA_STATE(xas, xa, i);
+			unsigned int seen = 0;
+			void *entry;
+
+			XA_BUG_ON(xa, !xa_get_mark(xa, i, XA_MARK_0));
+			XA_BUG_ON(xa, xa_get_mark(xa, i, XA_MARK_1));
+			XA_BUG_ON(xa, !xa_get_mark(xa, i, XA_MARK_2));
+
+			/* We should see two elements in the array */
+			rcu_read_lock();
+			xas_for_each(&xas, entry, ULONG_MAX)
+				seen++;
+			rcu_read_unlock();
+			XA_BUG_ON(xa, seen != 2);
+
+			/* One of which is marked */
+			xas_set(&xas, 0);
+			seen = 0;
+			rcu_read_lock();
+			xas_for_each_marked(&xas, entry, ULONG_MAX, XA_MARK_0)
+				seen++;
+			rcu_read_unlock();
+			XA_BUG_ON(xa, seen != 1);
+		}
+		XA_BUG_ON(xa, xa_get_mark(xa, next, XA_MARK_0));
+		XA_BUG_ON(xa, xa_get_mark(xa, next, XA_MARK_1));
+		XA_BUG_ON(xa, xa_get_mark(xa, next, XA_MARK_2));
+		xa_erase_index(xa, index);
+		xa_erase_index(xa, next);
+		XA_BUG_ON(xa, !xa_empty(xa));
+	}
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_xa_mark_2(struct xarray *xa)
+{
+	XA_STATE(xas, xa, 0);
+	unsigned long index;
+	unsigned int count = 0;
+	void *entry;
+
+	xa_store_index(xa, 0, GFP_KERNEL);
+	xa_set_mark(xa, 0, XA_MARK_0);
+	xas_lock(&xas);
+	xas_load(&xas);
+	xas_init_marks(&xas);
+	xas_unlock(&xas);
+	XA_BUG_ON(xa, !xa_get_mark(xa, 0, XA_MARK_0) == 0);
+
+	for (index = 3500; index < 4500; index++) {
+		xa_store_index(xa, index, GFP_KERNEL);
+		xa_set_mark(xa, index, XA_MARK_0);
+	}
+
+	xas_reset(&xas);
+	rcu_read_lock();
+	xas_for_each_marked(&xas, entry, ULONG_MAX, XA_MARK_0)
+		count++;
+	rcu_read_unlock();
+	XA_BUG_ON(xa, count != 1000);
+
+	xas_lock(&xas);
+	xas_for_each(&xas, entry, ULONG_MAX) {
+		xas_init_marks(&xas);
+		XA_BUG_ON(xa, !xa_get_mark(xa, xas.xa_index, XA_MARK_0));
+		XA_BUG_ON(xa, !xas_get_mark(&xas, XA_MARK_0));
+	}
+	xas_unlock(&xas);
+
+	xa_destroy(xa);
+}
+
+static noinline void check_xa_mark_3(struct xarray *xa)
+{
+#ifdef CONFIG_XARRAY_MULTI
+	XA_STATE(xas, xa, 0x41);
+	void *entry;
+	int count = 0;
+
+	xa_store_order(xa, 0x40, 2, xa_mk_index(0x40), GFP_KERNEL);
+	xa_set_mark(xa, 0x41, XA_MARK_0);
+
+	rcu_read_lock();
+	xas_for_each_marked(&xas, entry, ULONG_MAX, XA_MARK_0) {
+		count++;
+		XA_BUG_ON(xa, entry != xa_mk_index(0x40));
+	}
+	XA_BUG_ON(xa, count != 1);
+	rcu_read_unlock();
+	xa_destroy(xa);
+#endif
+}
+
+static noinline void check_xa_mark(struct xarray *xa)
+{
+	unsigned long index;
+
+	for (index = 0; index < 16384; index += 4)
+		check_xa_mark_1(xa, index);
+
+	check_xa_mark_2(xa);
+	check_xa_mark_3(xa);
+}
+
+static noinline void check_xa_shrink(struct xarray *xa)
+{
+	XA_STATE(xas, xa, 1);
+	struct xa_node *node;
+	unsigned int order;
+	unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 15 : 1;
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+	XA_BUG_ON(xa, xa_store_index(xa, 0, GFP_KERNEL) != NULL);
+	XA_BUG_ON(xa, xa_store_index(xa, 1, GFP_KERNEL) != NULL);
+
+	/*
+	 * Check that erasing the entry at 1 shrinks the tree and properly
+	 * marks the node as being deleted.
+	 */
+	xas_lock(&xas);
+	XA_BUG_ON(xa, xas_load(&xas) != xa_mk_value(1));
+	node = xas.xa_node;
+	XA_BUG_ON(xa, xa_entry_locked(xa, node, 0) != xa_mk_value(0));
+	XA_BUG_ON(xa, xas_store(&xas, NULL) != xa_mk_value(1));
+	XA_BUG_ON(xa, xa_load(xa, 1) != NULL);
+	XA_BUG_ON(xa, xas.xa_node != XAS_BOUNDS);
+	XA_BUG_ON(xa, xa_entry_locked(xa, node, 0) != XA_RETRY_ENTRY);
+	XA_BUG_ON(xa, xas_load(&xas) != NULL);
+	xas_unlock(&xas);
+	XA_BUG_ON(xa, xa_load(xa, 0) != xa_mk_value(0));
+	xa_erase_index(xa, 0);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	for (order = 0; order < max_order; order++) {
+		unsigned long max = (1UL << order) - 1;
+		xa_store_order(xa, 0, order, xa_mk_value(0), GFP_KERNEL);
+		XA_BUG_ON(xa, xa_load(xa, max) != xa_mk_value(0));
+		XA_BUG_ON(xa, xa_load(xa, max + 1) != NULL);
+		rcu_read_lock();
+		node = xa_head(xa);
+		rcu_read_unlock();
+		XA_BUG_ON(xa, xa_store_index(xa, ULONG_MAX, GFP_KERNEL) !=
+				NULL);
+		rcu_read_lock();
+		XA_BUG_ON(xa, xa_head(xa) == node);
+		rcu_read_unlock();
+		XA_BUG_ON(xa, xa_load(xa, max + 1) != NULL);
+		xa_erase_index(xa, ULONG_MAX);
+		XA_BUG_ON(xa, xa->xa_head != node);
+		xa_erase_index(xa, 0);
+	}
+}
+
+static noinline void check_insert(struct xarray *xa)
+{
+	unsigned long i;
+
+	for (i = 0; i < 1024; i++) {
+		xa_insert_index(xa, i);
+		XA_BUG_ON(xa, xa_load(xa, i - 1) != NULL);
+		XA_BUG_ON(xa, xa_load(xa, i + 1) != NULL);
+		xa_erase_index(xa, i);
+	}
+
+	for (i = 10; i < BITS_PER_LONG; i++) {
+		xa_insert_index(xa, 1UL << i);
+		XA_BUG_ON(xa, xa_load(xa, (1UL << i) - 1) != NULL);
+		XA_BUG_ON(xa, xa_load(xa, (1UL << i) + 1) != NULL);
+		xa_erase_index(xa, 1UL << i);
+
+		xa_insert_index(xa, (1UL << i) - 1);
+		XA_BUG_ON(xa, xa_load(xa, (1UL << i) - 2) != NULL);
+		XA_BUG_ON(xa, xa_load(xa, 1UL << i) != NULL);
+		xa_erase_index(xa, (1UL << i) - 1);
+	}
+
+	xa_insert_index(xa, ~0UL);
+	XA_BUG_ON(xa, xa_load(xa, 0UL) != NULL);
+	XA_BUG_ON(xa, xa_load(xa, ~1UL) != NULL);
+	xa_erase_index(xa, ~0UL);
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_cmpxchg(struct xarray *xa)
+{
+	void *FIVE = xa_mk_value(5);
+	void *SIX = xa_mk_value(6);
+	void *LOTS = xa_mk_value(12345678);
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+	XA_BUG_ON(xa, xa_store_index(xa, 12345678, GFP_KERNEL) != NULL);
+	XA_BUG_ON(xa, xa_insert(xa, 12345678, xa, GFP_KERNEL) != -EBUSY);
+	XA_BUG_ON(xa, xa_cmpxchg(xa, 12345678, SIX, FIVE, GFP_KERNEL) != LOTS);
+	XA_BUG_ON(xa, xa_cmpxchg(xa, 12345678, LOTS, FIVE, GFP_KERNEL) != LOTS);
+	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));
+}
+
+static noinline void check_cmpxchg_order(struct xarray *xa)
+{
+#ifdef CONFIG_XARRAY_MULTI
+	void *FIVE = xa_mk_value(5);
+	unsigned int i, order = 3;
+
+	XA_BUG_ON(xa, xa_store_order(xa, 0, order, FIVE, GFP_KERNEL));
+
+	/* Check entry FIVE has the order saved */
+	XA_BUG_ON(xa, xa_get_order(xa, xa_to_value(FIVE)) != order);
+
+	/* Check all the tied indexes have the same entry and order */
+	for (i = 0; i < (1 << order); i++) {
+		XA_BUG_ON(xa, xa_load(xa, i) != FIVE);
+		XA_BUG_ON(xa, xa_get_order(xa, i) != order);
+	}
+
+	/* Ensure that nothing is stored at index '1 << order' */
+	XA_BUG_ON(xa, xa_load(xa, 1 << order) != NULL);
+
+	/*
+	 * Additionally, keep the node information and the order at
+	 * '1 << order'
+	 */
+	XA_BUG_ON(xa, xa_store_order(xa, 1 << order, order, FIVE, GFP_KERNEL));
+	for (i = (1 << order); i < (1 << order) + (1 << order) - 1; i++) {
+		XA_BUG_ON(xa, xa_load(xa, i) != FIVE);
+		XA_BUG_ON(xa, xa_get_order(xa, i) != order);
+	}
+
+	/* Conditionally replace FIVE entry at index '0' with NULL */
+	XA_BUG_ON(xa, xa_cmpxchg(xa, 0, FIVE, NULL, GFP_KERNEL) != FIVE);
+
+	/* Verify the order is lost at FIVE (and old) entries */
+	XA_BUG_ON(xa, xa_get_order(xa, xa_to_value(FIVE)) != 0);
+
+	/* Verify the order and entries are lost in all the tied indexes */
+	for (i = 0; i < (1 << order); i++) {
+		XA_BUG_ON(xa, xa_load(xa, i) != NULL);
+		XA_BUG_ON(xa, xa_get_order(xa, i) != 0);
+	}
+
+	/* Verify node and order are kept at '1 << order' */
+	for (i = (1 << order); i < (1 << order) + (1 << order) - 1; i++) {
+		XA_BUG_ON(xa, xa_load(xa, i) != FIVE);
+		XA_BUG_ON(xa, xa_get_order(xa, i) != order);
+	}
+
+	xa_store_order(xa, 0, BITS_PER_LONG - 1, NULL, GFP_KERNEL);
+	XA_BUG_ON(xa, !xa_empty(xa));
+#endif
+}
+
+static noinline void check_reserve(struct xarray *xa)
+{
+	void *entry;
+	unsigned long index;
+	int count;
+
+	/* An array with a reserved entry is not empty */
+	XA_BUG_ON(xa, !xa_empty(xa));
+	XA_BUG_ON(xa, xa_reserve(xa, 12345678, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, xa_empty(xa));
+	XA_BUG_ON(xa, xa_load(xa, 12345678));
+	xa_release(xa, 12345678);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* Releasing a used entry does nothing */
+	XA_BUG_ON(xa, xa_reserve(xa, 12345678, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, xa_store_index(xa, 12345678, GFP_NOWAIT) != NULL);
+	xa_release(xa, 12345678);
+	xa_erase_index(xa, 12345678);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* cmpxchg sees a reserved entry as ZERO */
+	XA_BUG_ON(xa, xa_reserve(xa, 12345678, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, xa_cmpxchg(xa, 12345678, XA_ZERO_ENTRY,
+				xa_mk_value(12345678), GFP_NOWAIT) != NULL);
+	xa_release(xa, 12345678);
+	xa_erase_index(xa, 12345678);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* xa_insert treats it as busy */
+	XA_BUG_ON(xa, xa_reserve(xa, 12345678, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, xa_insert(xa, 12345678, xa_mk_value(12345678), 0) !=
+			-EBUSY);
+	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 */
+	xa_store_index(xa, 5, GFP_KERNEL);
+	XA_BUG_ON(xa, xa_reserve(xa, 6, GFP_KERNEL) != 0);
+	xa_store_index(xa, 7, GFP_KERNEL);
+
+	count = 0;
+	xa_for_each(xa, index, entry) {
+		XA_BUG_ON(xa, index != 5 && index != 7);
+		count++;
+	}
+	XA_BUG_ON(xa, count != 2);
+
+	/* If we free a reserved entry, we should be able to allocate it */
+	if (xa->xa_flags & XA_FLAGS_ALLOC) {
+		u32 id;
+
+		XA_BUG_ON(xa, xa_alloc(xa, &id, xa_mk_value(8),
+					XA_LIMIT(5, 10), GFP_KERNEL) != 0);
+		XA_BUG_ON(xa, id != 8);
+
+		xa_release(xa, 6);
+		XA_BUG_ON(xa, xa_alloc(xa, &id, xa_mk_value(6),
+					XA_LIMIT(5, 10), GFP_KERNEL) != 0);
+		XA_BUG_ON(xa, id != 6);
+	}
+
+	xa_destroy(xa);
+}
+
+static noinline void check_xas_erase(struct xarray *xa)
+{
+	XA_STATE(xas, xa, 0);
+	void *entry;
+	unsigned long i, j;
+
+	for (i = 0; i < 200; i++) {
+		for (j = i; j < 2 * i + 17; j++) {
+			xas_set(&xas, j);
+			do {
+				xas_lock(&xas);
+				xas_store(&xas, xa_mk_index(j));
+				xas_unlock(&xas);
+			} while (xas_nomem(&xas, GFP_KERNEL));
+		}
+
+		xas_set(&xas, ULONG_MAX);
+		do {
+			xas_lock(&xas);
+			xas_store(&xas, xa_mk_value(0));
+			xas_unlock(&xas);
+		} while (xas_nomem(&xas, GFP_KERNEL));
+
+		xas_lock(&xas);
+		xas_store(&xas, NULL);
+
+		xas_set(&xas, 0);
+		j = i;
+		xas_for_each(&xas, entry, ULONG_MAX) {
+			XA_BUG_ON(xa, entry != xa_mk_index(j));
+			xas_store(&xas, NULL);
+			j++;
+		}
+		xas_unlock(&xas);
+		XA_BUG_ON(xa, !xa_empty(xa));
+	}
+}
+
+#ifdef CONFIG_XARRAY_MULTI
+static noinline void check_multi_store_1(struct xarray *xa, unsigned long index,
+		unsigned int order)
+{
+	XA_STATE(xas, xa, index);
+	unsigned long min = index & ~((1UL << order) - 1);
+	unsigned long max = min + (1UL << order);
+
+	xa_store_order(xa, index, order, xa_mk_index(index), GFP_KERNEL);
+	XA_BUG_ON(xa, xa_load(xa, min) != xa_mk_index(index));
+	XA_BUG_ON(xa, xa_load(xa, max - 1) != xa_mk_index(index));
+	XA_BUG_ON(xa, xa_load(xa, max) != NULL);
+	XA_BUG_ON(xa, xa_load(xa, min - 1) != NULL);
+
+	xas_lock(&xas);
+	XA_BUG_ON(xa, xas_store(&xas, xa_mk_index(min)) != xa_mk_index(index));
+	xas_unlock(&xas);
+	XA_BUG_ON(xa, xa_load(xa, min) != xa_mk_index(min));
+	XA_BUG_ON(xa, xa_load(xa, max - 1) != xa_mk_index(min));
+	XA_BUG_ON(xa, xa_load(xa, max) != NULL);
+	XA_BUG_ON(xa, xa_load(xa, min - 1) != NULL);
+
+	xa_erase_index(xa, min);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_multi_store_2(struct xarray *xa, unsigned long index,
+		unsigned int order)
+{
+	XA_STATE(xas, xa, index);
+	xa_store_order(xa, index, order, xa_mk_value(0), GFP_KERNEL);
+
+	xas_lock(&xas);
+	XA_BUG_ON(xa, xas_store(&xas, xa_mk_value(1)) != xa_mk_value(0));
+	XA_BUG_ON(xa, xas.xa_index != index);
+	XA_BUG_ON(xa, xas_store(&xas, NULL) != xa_mk_value(1));
+	xas_unlock(&xas);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_multi_store_3(struct xarray *xa, unsigned long index,
+		unsigned int order)
+{
+	XA_STATE(xas, xa, 0);
+	void *entry;
+	int n = 0;
+
+	xa_store_order(xa, index, order, xa_mk_index(index), GFP_KERNEL);
+
+	xas_lock(&xas);
+	xas_for_each(&xas, entry, ULONG_MAX) {
+		XA_BUG_ON(xa, entry != xa_mk_index(index));
+		n++;
+	}
+	XA_BUG_ON(xa, n != 1);
+	xas_set(&xas, index + 1);
+	xas_for_each(&xas, entry, ULONG_MAX) {
+		XA_BUG_ON(xa, entry != xa_mk_index(index));
+		n++;
+	}
+	XA_BUG_ON(xa, n != 2);
+	xas_unlock(&xas);
+
+	xa_destroy(xa);
+}
+#endif
+
+static noinline void check_multi_store(struct xarray *xa)
+{
+#ifdef CONFIG_XARRAY_MULTI
+	unsigned long i, j, k;
+	unsigned int max_order = (sizeof(long) == 4) ? 30 : 60;
+
+	/* Loading from any position returns the same value */
+	xa_store_order(xa, 0, 1, xa_mk_value(0), GFP_KERNEL);
+	XA_BUG_ON(xa, xa_load(xa, 0) != xa_mk_value(0));
+	XA_BUG_ON(xa, xa_load(xa, 1) != xa_mk_value(0));
+	XA_BUG_ON(xa, xa_load(xa, 2) != NULL);
+	rcu_read_lock();
+	XA_BUG_ON(xa, xa_to_node(xa_head(xa))->count != 2);
+	XA_BUG_ON(xa, xa_to_node(xa_head(xa))->nr_values != 2);
+	rcu_read_unlock();
+
+	/* Storing adjacent to the value does not alter the value */
+	xa_store(xa, 3, xa, GFP_KERNEL);
+	XA_BUG_ON(xa, xa_load(xa, 0) != xa_mk_value(0));
+	XA_BUG_ON(xa, xa_load(xa, 1) != xa_mk_value(0));
+	XA_BUG_ON(xa, xa_load(xa, 2) != NULL);
+	rcu_read_lock();
+	XA_BUG_ON(xa, xa_to_node(xa_head(xa))->count != 3);
+	XA_BUG_ON(xa, xa_to_node(xa_head(xa))->nr_values != 2);
+	rcu_read_unlock();
+
+	/* Overwriting multiple indexes works */
+	xa_store_order(xa, 0, 2, xa_mk_value(1), GFP_KERNEL);
+	XA_BUG_ON(xa, xa_load(xa, 0) != xa_mk_value(1));
+	XA_BUG_ON(xa, xa_load(xa, 1) != xa_mk_value(1));
+	XA_BUG_ON(xa, xa_load(xa, 2) != xa_mk_value(1));
+	XA_BUG_ON(xa, xa_load(xa, 3) != xa_mk_value(1));
+	XA_BUG_ON(xa, xa_load(xa, 4) != NULL);
+	rcu_read_lock();
+	XA_BUG_ON(xa, xa_to_node(xa_head(xa))->count != 4);
+	XA_BUG_ON(xa, xa_to_node(xa_head(xa))->nr_values != 4);
+	rcu_read_unlock();
+
+	/* We can erase multiple values with a single store */
+	xa_store_order(xa, 0, BITS_PER_LONG - 1, NULL, GFP_KERNEL);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* Even when the first slot is empty but the others aren't */
+	xa_store_index(xa, 1, GFP_KERNEL);
+	xa_store_index(xa, 2, GFP_KERNEL);
+	xa_store_order(xa, 0, 2, NULL, GFP_KERNEL);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	for (i = 0; i < max_order; i++) {
+		for (j = 0; j < max_order; j++) {
+			xa_store_order(xa, 0, i, xa_mk_index(i), GFP_KERNEL);
+			xa_store_order(xa, 0, j, xa_mk_index(j), GFP_KERNEL);
+
+			for (k = 0; k < max_order; k++) {
+				void *entry = xa_load(xa, (1UL << k) - 1);
+				if ((i < k) && (j < k))
+					XA_BUG_ON(xa, entry != NULL);
+				else
+					XA_BUG_ON(xa, entry != xa_mk_index(j));
+			}
+
+			xa_erase(xa, 0);
+			XA_BUG_ON(xa, !xa_empty(xa));
+		}
+	}
+
+	for (i = 0; i < 20; i++) {
+		check_multi_store_1(xa, 200, i);
+		check_multi_store_1(xa, 0, i);
+		check_multi_store_1(xa, (1UL << i) + 1, i);
+	}
+	check_multi_store_2(xa, 4095, 9);
+
+	for (i = 1; i < 20; i++) {
+		check_multi_store_3(xa, 0, i);
+		check_multi_store_3(xa, 1UL << i, i);
+	}
+#endif
+}
+
+#ifdef CONFIG_XARRAY_MULTI
+/* mimics page cache __filemap_add_folio() */
+static noinline void check_xa_multi_store_adv_add(struct xarray *xa,
+						  unsigned long index,
+						  unsigned int order,
+						  void *p)
+{
+	XA_STATE(xas, xa, index);
+	unsigned int nrpages = 1UL << order;
+
+	/* users are responsible for index alignemnt to the order when adding */
+	XA_BUG_ON(xa, index & (nrpages - 1));
+
+	xas_set_order(&xas, index, order);
+
+	do {
+		xas_lock_irq(&xas);
+		xas_store(&xas, p);
+		xas_unlock_irq(&xas);
+		/*
+		 * In our selftest case the only failure we can expect is for
+		 * there not to be enough memory as we're not mimicking the
+		 * entire page cache, so verify that's the only error we can run
+		 * into here. The xas_nomem() which follows will ensure to fix
+		 * that condition for us so to chug on on the loop.
+		 */
+		XA_BUG_ON(xa, xas_error(&xas) && xas_error(&xas) != -ENOMEM);
+	} while (xas_nomem(&xas, GFP_KERNEL));
+
+	XA_BUG_ON(xa, xas_error(&xas));
+	XA_BUG_ON(xa, xa_load(xa, index) != p);
+}
+
+/* mimics page_cache_delete() */
+static noinline void check_xa_multi_store_adv_del_entry(struct xarray *xa,
+							unsigned long index,
+							unsigned int order)
+{
+	XA_STATE(xas, xa, index);
+
+	xas_set_order(&xas, index, order);
+	xas_store(&xas, NULL);
+	xas_init_marks(&xas);
+}
+
+static noinline void check_xa_multi_store_adv_delete(struct xarray *xa,
+						     unsigned long index,
+						     unsigned int order)
+{
+	xa_lock_irq(xa);
+	check_xa_multi_store_adv_del_entry(xa, index, order);
+	xa_unlock_irq(xa);
+}
+
+/* mimics page cache filemap_get_entry() */
+static noinline void *test_get_entry(struct xarray *xa, unsigned long index)
+{
+	XA_STATE(xas, xa, index);
+	void *p;
+	static unsigned int loops = 0;
+
+	rcu_read_lock();
+repeat:
+	xas_reset(&xas);
+	p = xas_load(&xas);
+	if (xas_retry(&xas, p))
+		goto repeat;
+	rcu_read_unlock();
+
+	/*
+	 * This is not part of the page cache, this selftest is pretty
+	 * aggressive and does not want to trust the xarray API but rather
+	 * test it, and for order 20 (4 GiB block size) we can loop over
+	 * over a million entries which can cause a soft lockup. Page cache
+	 * APIs won't be stupid, proper page cache APIs loop over the proper
+	 * order so when using a larger order we skip shared entries.
+	 */
+	if (++loops % XA_CHECK_SCHED == 0)
+		schedule();
+
+	return p;
+}
+
+static unsigned long some_val = 0xdeadbeef;
+static unsigned long some_val_2 = 0xdeaddead;
+
+/* mimics the page cache usage */
+static noinline void check_xa_multi_store_adv(struct xarray *xa,
+					      unsigned long pos,
+					      unsigned int order)
+{
+	unsigned int nrpages = 1UL << order;
+	unsigned long index, base, next_index, next_next_index;
+	unsigned int i;
+
+	index = pos >> PAGE_SHIFT;
+	base = round_down(index, nrpages);
+	next_index = round_down(base + nrpages, nrpages);
+	next_next_index = round_down(next_index + nrpages, nrpages);
+
+	check_xa_multi_store_adv_add(xa, base, order, &some_val);
+
+	for (i = 0; i < nrpages; i++)
+		XA_BUG_ON(xa, test_get_entry(xa, base + i) != &some_val);
+
+	XA_BUG_ON(xa, test_get_entry(xa, next_index) != NULL);
+
+	/* Use order 0 for the next item */
+	check_xa_multi_store_adv_add(xa, next_index, 0, &some_val_2);
+	XA_BUG_ON(xa, test_get_entry(xa, next_index) != &some_val_2);
+
+	/* Remove the next item */
+	check_xa_multi_store_adv_delete(xa, next_index, 0);
+
+	/* Now use order for a new pointer */
+	check_xa_multi_store_adv_add(xa, next_index, order, &some_val_2);
+
+	for (i = 0; i < nrpages; i++)
+		XA_BUG_ON(xa, test_get_entry(xa, next_index + i) != &some_val_2);
+
+	check_xa_multi_store_adv_delete(xa, next_index, order);
+	check_xa_multi_store_adv_delete(xa, base, order);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* starting fresh again */
+
+	/* let's test some holes now */
+
+	/* hole at base and next_next */
+	check_xa_multi_store_adv_add(xa, next_index, order, &some_val_2);
+
+	for (i = 0; i < nrpages; i++)
+		XA_BUG_ON(xa, test_get_entry(xa, base + i) != NULL);
+
+	for (i = 0; i < nrpages; i++)
+		XA_BUG_ON(xa, test_get_entry(xa, next_index + i) != &some_val_2);
+
+	for (i = 0; i < nrpages; i++)
+		XA_BUG_ON(xa, test_get_entry(xa, next_next_index + i) != NULL);
+
+	check_xa_multi_store_adv_delete(xa, next_index, order);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* hole at base and next */
+
+	check_xa_multi_store_adv_add(xa, next_next_index, order, &some_val_2);
+
+	for (i = 0; i < nrpages; i++)
+		XA_BUG_ON(xa, test_get_entry(xa, base + i) != NULL);
+
+	for (i = 0; i < nrpages; i++)
+		XA_BUG_ON(xa, test_get_entry(xa, next_index + i) != NULL);
+
+	for (i = 0; i < nrpages; i++)
+		XA_BUG_ON(xa, test_get_entry(xa, next_next_index + i) != &some_val_2);
+
+	check_xa_multi_store_adv_delete(xa, next_next_index, order);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+#endif
+
+static noinline void check_multi_store_advanced(struct xarray *xa)
+{
+#ifdef CONFIG_XARRAY_MULTI
+	unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 20 : 1;
+	unsigned long end = ULONG_MAX/2;
+	unsigned long pos, i;
+
+	/*
+	 * About 117 million tests below.
+	 */
+	for (pos = 7; pos < end; pos = (pos * pos) + 564) {
+		for (i = 0; i < max_order; i++) {
+			check_xa_multi_store_adv(xa, pos, i);
+			check_xa_multi_store_adv(xa, pos + 157, i);
+		}
+	}
+#endif
+}
+
+static noinline void check_xa_alloc_1(struct xarray *xa, unsigned int base)
+{
+	int i;
+	u32 id;
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+	/* An empty array should assign %base to the first alloc */
+	xa_alloc_index(xa, base, GFP_KERNEL);
+
+	/* Erasing it should make the array empty again */
+	xa_erase_index(xa, base);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* And it should assign %base again */
+	xa_alloc_index(xa, base, GFP_KERNEL);
+
+	/* Allocating and then erasing a lot should not lose base */
+	for (i = base + 1; i < 2 * XA_CHUNK_SIZE; i++)
+		xa_alloc_index(xa, i, GFP_KERNEL);
+	for (i = base; i < 2 * XA_CHUNK_SIZE; i++)
+		xa_erase_index(xa, i);
+	xa_alloc_index(xa, base, GFP_KERNEL);
+
+	/* Destroying the array should do the same as erasing */
+	xa_destroy(xa);
+
+	/* And it should assign %base again */
+	xa_alloc_index(xa, base, GFP_KERNEL);
+
+	/* The next assigned ID should be base+1 */
+	xa_alloc_index(xa, base + 1, GFP_KERNEL);
+	xa_erase_index(xa, base + 1);
+
+	/* Storing a value should mark it used */
+	xa_store_index(xa, base + 1, GFP_KERNEL);
+	xa_alloc_index(xa, base + 2, GFP_KERNEL);
+
+	/* If we then erase base, it should be free */
+	xa_erase_index(xa, base);
+	xa_alloc_index(xa, base, GFP_KERNEL);
+
+	xa_erase_index(xa, base + 1);
+	xa_erase_index(xa, base + 2);
+
+	for (i = 1; i < 5000; i++) {
+		xa_alloc_index(xa, base + i, GFP_KERNEL);
+	}
+
+	xa_destroy(xa);
+
+	/* Check that we fail properly at the limit of allocation */
+	XA_BUG_ON(xa, xa_alloc(xa, &id, xa_mk_index(UINT_MAX - 1),
+				XA_LIMIT(UINT_MAX - 1, UINT_MAX),
+				GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, id != 0xfffffffeU);
+	XA_BUG_ON(xa, xa_alloc(xa, &id, xa_mk_index(UINT_MAX),
+				XA_LIMIT(UINT_MAX - 1, UINT_MAX),
+				GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, id != 0xffffffffU);
+	id = 3;
+	XA_BUG_ON(xa, xa_alloc(xa, &id, xa_mk_index(0),
+				XA_LIMIT(UINT_MAX - 1, UINT_MAX),
+				GFP_KERNEL) != -EBUSY);
+	XA_BUG_ON(xa, id != 3);
+	xa_destroy(xa);
+
+	XA_BUG_ON(xa, xa_alloc(xa, &id, xa_mk_index(10), XA_LIMIT(10, 5),
+				GFP_KERNEL) != -EBUSY);
+	XA_BUG_ON(xa, xa_store_index(xa, 3, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, xa_alloc(xa, &id, xa_mk_index(10), XA_LIMIT(10, 5),
+				GFP_KERNEL) != -EBUSY);
+	xa_erase_index(xa, 3);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_xa_alloc_2(struct xarray *xa, unsigned int base)
+{
+	unsigned int i, id;
+	unsigned long index;
+	void *entry;
+
+	/* Allocate and free a NULL and check xa_empty() behaves */
+	XA_BUG_ON(xa, !xa_empty(xa));
+	XA_BUG_ON(xa, xa_alloc(xa, &id, NULL, xa_limit_32b, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, id != base);
+	XA_BUG_ON(xa, xa_empty(xa));
+	XA_BUG_ON(xa, xa_erase(xa, id) != NULL);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* Ditto, but check destroy instead of erase */
+	XA_BUG_ON(xa, !xa_empty(xa));
+	XA_BUG_ON(xa, xa_alloc(xa, &id, NULL, xa_limit_32b, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, id != base);
+	XA_BUG_ON(xa, xa_empty(xa));
+	xa_destroy(xa);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	for (i = base; i < base + 10; i++) {
+		XA_BUG_ON(xa, xa_alloc(xa, &id, NULL, xa_limit_32b,
+					GFP_KERNEL) != 0);
+		XA_BUG_ON(xa, id != i);
+	}
+
+	XA_BUG_ON(xa, xa_store(xa, 3, xa_mk_index(3), GFP_KERNEL) != NULL);
+	XA_BUG_ON(xa, xa_store(xa, 4, xa_mk_index(4), GFP_KERNEL) != NULL);
+	XA_BUG_ON(xa, xa_store(xa, 4, NULL, GFP_KERNEL) != xa_mk_index(4));
+	XA_BUG_ON(xa, xa_erase(xa, 5) != NULL);
+	XA_BUG_ON(xa, xa_alloc(xa, &id, NULL, xa_limit_32b, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, id != 5);
+
+	xa_for_each(xa, index, entry) {
+		xa_erase_index(xa, index);
+	}
+
+	for (i = base; i < base + 9; i++) {
+		XA_BUG_ON(xa, xa_erase(xa, i) != NULL);
+		XA_BUG_ON(xa, xa_empty(xa));
+	}
+	XA_BUG_ON(xa, xa_erase(xa, 8) != NULL);
+	XA_BUG_ON(xa, xa_empty(xa));
+	XA_BUG_ON(xa, xa_erase(xa, base + 9) != NULL);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	xa_destroy(xa);
+}
+
+static noinline void check_xa_alloc_3(struct xarray *xa, unsigned int base)
+{
+	struct xa_limit limit = XA_LIMIT(1, 0x3fff);
+	u32 next = 0;
+	unsigned int i, id;
+	unsigned long index;
+	void *entry;
+	int ret;
+
+	XA_BUG_ON(xa, xa_alloc_cyclic(xa, &id, xa_mk_index(1), limit,
+				&next, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, id != 1);
+
+	next = 0x3ffd;
+	XA_BUG_ON(xa, xa_alloc_cyclic(xa, &id, xa_mk_index(0x3ffd), limit,
+				&next, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, id != 0x3ffd);
+	xa_erase_index(xa, 0x3ffd);
+	xa_erase_index(xa, 1);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	for (i = 0x3ffe; i < 0x4003; i++) {
+		if (i < 0x4000)
+			entry = xa_mk_index(i);
+		else
+			entry = xa_mk_index(i - 0x3fff);
+		XA_BUG_ON(xa, xa_alloc_cyclic(xa, &id, entry, limit,
+					&next, GFP_KERNEL) != 0);
+		XA_BUG_ON(xa, xa_mk_index(id) != entry);
+	}
+
+	/* Check wrap-around is handled correctly */
+	if (base != 0)
+		xa_erase_index(xa, base);
+	xa_erase_index(xa, base + 1);
+	next = UINT_MAX;
+	XA_BUG_ON(xa, xa_alloc_cyclic(xa, &id, xa_mk_index(UINT_MAX),
+				xa_limit_32b, &next, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, id != UINT_MAX);
+	XA_BUG_ON(xa, xa_alloc_cyclic(xa, &id, xa_mk_index(base),
+				xa_limit_32b, &next, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, id != base);
+	XA_BUG_ON(xa, xa_alloc_cyclic(xa, &id, xa_mk_index(base + 1),
+				xa_limit_32b, &next, GFP_KERNEL) != 0);
+	XA_BUG_ON(xa, id != base + 1);
+
+	xa_for_each(xa, index, entry)
+		xa_erase_index(xa, index);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* check wrap-around return of __xa_alloc_cyclic() */
+	next = UINT_MAX;
+	XA_BUG_ON(xa, xa_alloc_cyclic(xa, &id, xa_mk_index(UINT_MAX),
+				      xa_limit_32b, &next, GFP_KERNEL) != 0);
+	xa_lock(xa);
+	ret = __xa_alloc_cyclic(xa, &id, xa_mk_index(base), xa_limit_32b,
+				&next, GFP_KERNEL);
+	xa_unlock(xa);
+	XA_BUG_ON(xa, ret != 1);
+	xa_for_each(xa, index, entry)
+		xa_erase_index(xa, index);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static DEFINE_XARRAY_ALLOC(xa0);
+static DEFINE_XARRAY_ALLOC1(xa1);
+
+static noinline void check_xa_alloc(void)
+{
+	check_xa_alloc_1(&xa0, 0);
+	check_xa_alloc_1(&xa1, 1);
+	check_xa_alloc_2(&xa0, 0);
+	check_xa_alloc_2(&xa1, 1);
+	check_xa_alloc_3(&xa0, 0);
+	check_xa_alloc_3(&xa1, 1);
+}
+
+static noinline void __check_store_iter(struct xarray *xa, unsigned long start,
+			unsigned int order, unsigned int present)
+{
+	XA_STATE_ORDER(xas, xa, start, order);
+	void *entry;
+	unsigned int count = 0;
+
+retry:
+	xas_lock(&xas);
+	xas_for_each_conflict(&xas, entry) {
+		XA_BUG_ON(xa, !xa_is_value(entry));
+		XA_BUG_ON(xa, entry < xa_mk_index(start));
+		XA_BUG_ON(xa, entry > xa_mk_index(start + (1UL << order) - 1));
+		count++;
+	}
+	xas_store(&xas, xa_mk_index(start));
+	xas_unlock(&xas);
+	if (xas_nomem(&xas, GFP_KERNEL)) {
+		count = 0;
+		goto retry;
+	}
+	XA_BUG_ON(xa, xas_error(&xas));
+	XA_BUG_ON(xa, count != present);
+	XA_BUG_ON(xa, xa_load(xa, start) != xa_mk_index(start));
+	XA_BUG_ON(xa, xa_load(xa, start + (1UL << order) - 1) !=
+			xa_mk_index(start));
+	xa_erase_index(xa, start);
+}
+
+static noinline void check_store_iter(struct xarray *xa)
+{
+	unsigned int i, j;
+	unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 20 : 1;
+
+	for (i = 0; i < max_order; i++) {
+		unsigned int min = 1 << i;
+		unsigned int max = (2 << i) - 1;
+		__check_store_iter(xa, 0, i, 0);
+		XA_BUG_ON(xa, !xa_empty(xa));
+		__check_store_iter(xa, min, i, 0);
+		XA_BUG_ON(xa, !xa_empty(xa));
+
+		xa_store_index(xa, min, GFP_KERNEL);
+		__check_store_iter(xa, min, i, 1);
+		XA_BUG_ON(xa, !xa_empty(xa));
+		xa_store_index(xa, max, GFP_KERNEL);
+		__check_store_iter(xa, min, i, 1);
+		XA_BUG_ON(xa, !xa_empty(xa));
+
+		for (j = 0; j < min; j++)
+			xa_store_index(xa, j, GFP_KERNEL);
+		__check_store_iter(xa, 0, i, min);
+		XA_BUG_ON(xa, !xa_empty(xa));
+		for (j = 0; j < min; j++)
+			xa_store_index(xa, min + j, GFP_KERNEL);
+		__check_store_iter(xa, min, i, min);
+		XA_BUG_ON(xa, !xa_empty(xa));
+	}
+#ifdef CONFIG_XARRAY_MULTI
+	xa_store_index(xa, 63, GFP_KERNEL);
+	xa_store_index(xa, 65, GFP_KERNEL);
+	__check_store_iter(xa, 64, 2, 1);
+	xa_erase_index(xa, 63);
+#endif
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_multi_find_1(struct xarray *xa, unsigned order)
+{
+#ifdef CONFIG_XARRAY_MULTI
+	unsigned long multi = 3 << order;
+	unsigned long next = 4 << order;
+	unsigned long index;
+
+	xa_store_order(xa, multi, order, xa_mk_value(multi), GFP_KERNEL);
+	XA_BUG_ON(xa, xa_store_index(xa, next, GFP_KERNEL) != NULL);
+	XA_BUG_ON(xa, xa_store_index(xa, next + 1, GFP_KERNEL) != NULL);
+
+	index = 0;
+	XA_BUG_ON(xa, xa_find(xa, &index, ULONG_MAX, XA_PRESENT) !=
+			xa_mk_value(multi));
+	XA_BUG_ON(xa, index != multi);
+	index = multi + 1;
+	XA_BUG_ON(xa, xa_find(xa, &index, ULONG_MAX, XA_PRESENT) !=
+			xa_mk_value(multi));
+	XA_BUG_ON(xa, (index < multi) || (index >= next));
+	XA_BUG_ON(xa, xa_find_after(xa, &index, ULONG_MAX, XA_PRESENT) !=
+			xa_mk_value(next));
+	XA_BUG_ON(xa, index != next);
+	XA_BUG_ON(xa, xa_find_after(xa, &index, next, XA_PRESENT) != NULL);
+	XA_BUG_ON(xa, index != next);
+
+	xa_erase_index(xa, multi);
+	xa_erase_index(xa, next);
+	xa_erase_index(xa, next + 1);
+	XA_BUG_ON(xa, !xa_empty(xa));
+#endif
+}
+
+static noinline void check_multi_find_2(struct xarray *xa)
+{
+	unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 10 : 1;
+	unsigned int i, j;
+	void *entry;
+
+	for (i = 0; i < max_order; i++) {
+		unsigned long index = 1UL << i;
+		for (j = 0; j < index; j++) {
+			XA_STATE(xas, xa, j + index);
+			xa_store_index(xa, index - 1, GFP_KERNEL);
+			xa_store_order(xa, index, i, xa_mk_index(index),
+					GFP_KERNEL);
+			rcu_read_lock();
+			xas_for_each(&xas, entry, ULONG_MAX) {
+				xa_erase_index(xa, index);
+			}
+			rcu_read_unlock();
+			xa_erase_index(xa, index - 1);
+			XA_BUG_ON(xa, !xa_empty(xa));
+		}
+	}
+}
+
+static noinline void check_multi_find_3(struct xarray *xa)
+{
+	unsigned int order;
+
+	for (order = 5; order < order_limit; order++) {
+		unsigned long index = 1UL << (order - 5);
+
+		XA_BUG_ON(xa, !xa_empty(xa));
+		xa_store_order(xa, 0, order - 4, xa_mk_index(0), GFP_KERNEL);
+		XA_BUG_ON(xa, xa_find_after(xa, &index, ULONG_MAX, XA_PRESENT));
+		xa_erase_index(xa, 0);
+	}
+}
+
+static noinline void check_find_1(struct xarray *xa)
+{
+	unsigned long i, j, k;
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/*
+	 * Check xa_find with all pairs between 0 and 99 inclusive,
+	 * starting at every index between 0 and 99
+	 */
+	for (i = 0; i < 100; i++) {
+		XA_BUG_ON(xa, xa_store_index(xa, i, GFP_KERNEL) != NULL);
+		xa_set_mark(xa, i, XA_MARK_0);
+		for (j = 0; j < i; j++) {
+			XA_BUG_ON(xa, xa_store_index(xa, j, GFP_KERNEL) !=
+					NULL);
+			xa_set_mark(xa, j, XA_MARK_0);
+			for (k = 0; k < 100; k++) {
+				unsigned long index = k;
+				void *entry = xa_find(xa, &index, ULONG_MAX,
+								XA_PRESENT);
+				if (k <= j)
+					XA_BUG_ON(xa, index != j);
+				else if (k <= i)
+					XA_BUG_ON(xa, index != i);
+				else
+					XA_BUG_ON(xa, entry != NULL);
+
+				index = k;
+				entry = xa_find(xa, &index, ULONG_MAX,
+								XA_MARK_0);
+				if (k <= j)
+					XA_BUG_ON(xa, index != j);
+				else if (k <= i)
+					XA_BUG_ON(xa, index != i);
+				else
+					XA_BUG_ON(xa, entry != NULL);
+			}
+			xa_erase_index(xa, j);
+			XA_BUG_ON(xa, xa_get_mark(xa, j, XA_MARK_0));
+			XA_BUG_ON(xa, !xa_get_mark(xa, i, XA_MARK_0));
+		}
+		xa_erase_index(xa, i);
+		XA_BUG_ON(xa, xa_get_mark(xa, i, XA_MARK_0));
+	}
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_find_2(struct xarray *xa)
+{
+	void *entry;
+	unsigned long i, j, index;
+
+	xa_for_each(xa, index, entry) {
+		XA_BUG_ON(xa, true);
+	}
+
+	for (i = 0; i < 1024; i++) {
+		xa_store_index(xa, index, GFP_KERNEL);
+		j = 0;
+		xa_for_each(xa, index, entry) {
+			XA_BUG_ON(xa, xa_mk_index(index) != entry);
+			XA_BUG_ON(xa, index != j++);
+		}
+	}
+
+	xa_destroy(xa);
+}
+
+static noinline void check_find_3(struct xarray *xa)
+{
+	XA_STATE(xas, xa, 0);
+	unsigned long i, j, k;
+	void *entry;
+
+	for (i = 0; i < 100; i++) {
+		for (j = 0; j < 100; j++) {
+			rcu_read_lock();
+			for (k = 0; k < 100; k++) {
+				xas_set(&xas, j);
+				xas_for_each_marked(&xas, entry, k, XA_MARK_0)
+					;
+				if (j > k)
+					XA_BUG_ON(xa,
+						xas.xa_node != XAS_RESTART);
+			}
+			rcu_read_unlock();
+		}
+		xa_store_index(xa, i, GFP_KERNEL);
+		xa_set_mark(xa, i, XA_MARK_0);
+	}
+	xa_destroy(xa);
+}
+
+static noinline void check_find_4(struct xarray *xa)
+{
+	unsigned long index = 0;
+	void *entry;
+
+	xa_store_index(xa, ULONG_MAX, GFP_KERNEL);
+
+	entry = xa_find_after(xa, &index, ULONG_MAX, XA_PRESENT);
+	XA_BUG_ON(xa, entry != xa_mk_index(ULONG_MAX));
+
+	entry = xa_find_after(xa, &index, ULONG_MAX, XA_PRESENT);
+	XA_BUG_ON(xa, entry);
+
+	xa_erase_index(xa, ULONG_MAX);
+}
+
+static noinline void check_find(struct xarray *xa)
+{
+	unsigned i;
+
+	check_find_1(xa);
+	check_find_2(xa);
+	check_find_3(xa);
+	check_find_4(xa);
+
+	for (i = 2; i < 10; i++)
+		check_multi_find_1(xa, i);
+	check_multi_find_2(xa);
+	check_multi_find_3(xa);
+}
+
+/* See find_swap_entry() in mm/shmem.c */
+static noinline unsigned long xa_find_entry(struct xarray *xa, void *item)
+{
+	XA_STATE(xas, xa, 0);
+	unsigned int checked = 0;
+	void *entry;
+
+	rcu_read_lock();
+	xas_for_each(&xas, entry, ULONG_MAX) {
+		if (xas_retry(&xas, entry))
+			continue;
+		if (entry == item)
+			break;
+		checked++;
+		if ((checked % 4) != 0)
+			continue;
+		xas_pause(&xas);
+	}
+	rcu_read_unlock();
+
+	return entry ? xas.xa_index : -1;
+}
+
+static noinline void check_find_entry(struct xarray *xa)
+{
+#ifdef CONFIG_XARRAY_MULTI
+	unsigned int order;
+	unsigned long offset, index;
+
+	for (order = 0; order < 20; order++) {
+		for (offset = 0; offset < (1UL << (order + 3));
+		     offset += (1UL << order)) {
+			for (index = 0; index < (1UL << (order + 5));
+			     index += (1UL << order)) {
+				xa_store_order(xa, index, order,
+						xa_mk_index(index), GFP_KERNEL);
+				XA_BUG_ON(xa, xa_load(xa, index) !=
+						xa_mk_index(index));
+				XA_BUG_ON(xa, xa_find_entry(xa,
+						xa_mk_index(index)) != index);
+			}
+			XA_BUG_ON(xa, xa_find_entry(xa, xa) != -1);
+			xa_destroy(xa);
+		}
+	}
+#endif
+
+	XA_BUG_ON(xa, xa_find_entry(xa, xa) != -1);
+	xa_store_index(xa, ULONG_MAX, GFP_KERNEL);
+	XA_BUG_ON(xa, xa_find_entry(xa, xa) != -1);
+	XA_BUG_ON(xa, xa_find_entry(xa, xa_mk_index(ULONG_MAX)) != -1);
+	xa_erase_index(xa, ULONG_MAX);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_pause(struct xarray *xa)
+{
+	XA_STATE(xas, xa, 0);
+	void *entry;
+	int order;
+	unsigned long index = 1;
+	unsigned int count = 0;
+
+	for (order = 0; order < order_limit; order++) {
+		XA_BUG_ON(xa, xa_store_order(xa, index, order,
+					xa_mk_index(index), GFP_KERNEL));
+		index += 1UL << order;
+	}
+
+	rcu_read_lock();
+	xas_for_each(&xas, entry, ULONG_MAX) {
+		XA_BUG_ON(xa, entry != xa_mk_index(1UL << count));
+		count++;
+	}
+	rcu_read_unlock();
+	XA_BUG_ON(xa, count != order_limit);
+
+	count = 0;
+	xas_set(&xas, 0);
+	rcu_read_lock();
+	xas_for_each(&xas, entry, ULONG_MAX) {
+		XA_BUG_ON(xa, entry != xa_mk_index(1UL << count));
+		count++;
+		xas_pause(&xas);
+	}
+	rcu_read_unlock();
+	XA_BUG_ON(xa, count != order_limit);
+
+	xa_destroy(xa);
+
+	index = 0;
+	for (order = order_limit - 1; order >= 0; order--) {
+		XA_BUG_ON(xa, xa_store_order(xa, index, order,
+					xa_mk_index(index), GFP_KERNEL));
+		index += 1UL << order;
+	}
+
+	index = 0;
+	count = 0;
+	xas_set(&xas, 0);
+	rcu_read_lock();
+	xas_for_each(&xas, entry, ULONG_MAX) {
+		XA_BUG_ON(xa, entry != xa_mk_index(index));
+		index += 1UL << (order_limit - count - 1);
+		count++;
+	}
+	rcu_read_unlock();
+	XA_BUG_ON(xa, count != order_limit);
+
+	index = 0;
+	count = 0;
+	/* test unaligned index */
+	xas_set(&xas, 1 % (1UL << (order_limit - 1)));
+	rcu_read_lock();
+	xas_for_each(&xas, entry, ULONG_MAX) {
+		XA_BUG_ON(xa, entry != xa_mk_index(index));
+		index += 1UL << (order_limit - count - 1);
+		count++;
+		xas_pause(&xas);
+	}
+	rcu_read_unlock();
+	XA_BUG_ON(xa, count != order_limit);
+
+	xa_destroy(xa);
+
+}
+
+static noinline void check_move_tiny(struct xarray *xa)
+{
+	XA_STATE(xas, xa, 0);
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+	rcu_read_lock();
+	XA_BUG_ON(xa, xas_next(&xas) != NULL);
+	XA_BUG_ON(xa, xas_next(&xas) != NULL);
+	rcu_read_unlock();
+	xa_store_index(xa, 0, GFP_KERNEL);
+	rcu_read_lock();
+	xas_set(&xas, 0);
+	XA_BUG_ON(xa, xas_next(&xas) != xa_mk_index(0));
+	XA_BUG_ON(xa, xas_next(&xas) != NULL);
+	xas_set(&xas, 0);
+	XA_BUG_ON(xa, xas_prev(&xas) != xa_mk_index(0));
+	XA_BUG_ON(xa, xas_prev(&xas) != NULL);
+	rcu_read_unlock();
+	xa_erase_index(xa, 0);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_move_max(struct xarray *xa)
+{
+	XA_STATE(xas, xa, 0);
+
+	xa_store_index(xa, ULONG_MAX, GFP_KERNEL);
+	rcu_read_lock();
+	XA_BUG_ON(xa, xas_find(&xas, ULONG_MAX) != xa_mk_index(ULONG_MAX));
+	XA_BUG_ON(xa, xas_find(&xas, ULONG_MAX) != NULL);
+	rcu_read_unlock();
+
+	xas_set(&xas, 0);
+	rcu_read_lock();
+	XA_BUG_ON(xa, xas_find(&xas, ULONG_MAX) != xa_mk_index(ULONG_MAX));
+	xas_pause(&xas);
+	XA_BUG_ON(xa, xas_find(&xas, ULONG_MAX) != NULL);
+	rcu_read_unlock();
+
+	xa_erase_index(xa, ULONG_MAX);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_move_small(struct xarray *xa, unsigned long idx)
+{
+	XA_STATE(xas, xa, 0);
+	unsigned long i;
+
+	xa_store_index(xa, 0, GFP_KERNEL);
+	xa_store_index(xa, idx, GFP_KERNEL);
+
+	rcu_read_lock();
+	for (i = 0; i < idx * 4; i++) {
+		void *entry = xas_next(&xas);
+		if (i <= idx)
+			XA_BUG_ON(xa, xas.xa_node == XAS_RESTART);
+		XA_BUG_ON(xa, xas.xa_index != i);
+		if (i == 0 || i == idx)
+			XA_BUG_ON(xa, entry != xa_mk_index(i));
+		else
+			XA_BUG_ON(xa, entry != NULL);
+	}
+	xas_next(&xas);
+	XA_BUG_ON(xa, xas.xa_index != i);
+
+	do {
+		void *entry = xas_prev(&xas);
+		i--;
+		if (i <= idx)
+			XA_BUG_ON(xa, xas.xa_node == XAS_RESTART);
+		XA_BUG_ON(xa, xas.xa_index != i);
+		if (i == 0 || i == idx)
+			XA_BUG_ON(xa, entry != xa_mk_index(i));
+		else
+			XA_BUG_ON(xa, entry != NULL);
+	} while (i > 0);
+
+	xas_set(&xas, ULONG_MAX);
+	XA_BUG_ON(xa, xas_next(&xas) != NULL);
+	XA_BUG_ON(xa, xas.xa_index != ULONG_MAX);
+	XA_BUG_ON(xa, xas_next(&xas) != xa_mk_value(0));
+	XA_BUG_ON(xa, xas.xa_index != 0);
+	XA_BUG_ON(xa, xas_prev(&xas) != NULL);
+	XA_BUG_ON(xa, xas.xa_index != ULONG_MAX);
+	rcu_read_unlock();
+
+	xa_erase_index(xa, 0);
+	xa_erase_index(xa, idx);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_move(struct xarray *xa)
+{
+	XA_STATE(xas, xa, (1 << 16) - 1);
+	unsigned long i;
+
+	for (i = 0; i < (1 << 16); i++)
+		XA_BUG_ON(xa, xa_store_index(xa, i, GFP_KERNEL) != NULL);
+
+	rcu_read_lock();
+	do {
+		void *entry = xas_prev(&xas);
+		i--;
+		XA_BUG_ON(xa, entry != xa_mk_index(i));
+		XA_BUG_ON(xa, i != xas.xa_index);
+	} while (i != 0);
+
+	XA_BUG_ON(xa, xas_prev(&xas) != NULL);
+	XA_BUG_ON(xa, xas.xa_index != ULONG_MAX);
+
+	do {
+		void *entry = xas_next(&xas);
+		XA_BUG_ON(xa, entry != xa_mk_index(i));
+		XA_BUG_ON(xa, i != xas.xa_index);
+		i++;
+	} while (i < (1 << 16));
+	rcu_read_unlock();
+
+	for (i = (1 << 8); i < (1 << 15); i++)
+		xa_erase_index(xa, i);
+
+	i = xas.xa_index;
+
+	rcu_read_lock();
+	do {
+		void *entry = xas_prev(&xas);
+		i--;
+		if ((i < (1 << 8)) || (i >= (1 << 15)))
+			XA_BUG_ON(xa, entry != xa_mk_index(i));
+		else
+			XA_BUG_ON(xa, entry != NULL);
+		XA_BUG_ON(xa, i != xas.xa_index);
+	} while (i != 0);
+
+	XA_BUG_ON(xa, xas_prev(&xas) != NULL);
+	XA_BUG_ON(xa, xas.xa_index != ULONG_MAX);
+
+	do {
+		void *entry = xas_next(&xas);
+		if ((i < (1 << 8)) || (i >= (1 << 15)))
+			XA_BUG_ON(xa, entry != xa_mk_index(i));
+		else
+			XA_BUG_ON(xa, entry != NULL);
+		XA_BUG_ON(xa, i != xas.xa_index);
+		i++;
+	} while (i < (1 << 16));
+	rcu_read_unlock();
+
+	xa_destroy(xa);
+
+	check_move_tiny(xa);
+	check_move_max(xa);
+
+	for (i = 0; i < 16; i++)
+		check_move_small(xa, 1UL << i);
+
+	for (i = 2; i < 16; i++)
+		check_move_small(xa, (1UL << i) - 1);
+}
+
+static noinline void xa_store_many_order(struct xarray *xa,
+		unsigned long index, unsigned order)
+{
+	XA_STATE_ORDER(xas, xa, index, order);
+	unsigned int i = 0;
+
+	do {
+		xas_lock(&xas);
+		XA_BUG_ON(xa, xas_find_conflict(&xas));
+		xas_create_range(&xas);
+		if (xas_error(&xas))
+			goto unlock;
+		for (i = 0; i < (1U << order); i++) {
+			XA_BUG_ON(xa, xas_store(&xas, xa_mk_index(index + i)));
+			xas_next(&xas);
+		}
+unlock:
+		xas_unlock(&xas);
+	} while (xas_nomem(&xas, GFP_KERNEL));
+
+	XA_BUG_ON(xa, xas_error(&xas));
+}
+
+static noinline void check_create_range_1(struct xarray *xa,
+		unsigned long index, unsigned order)
+{
+	unsigned long i;
+
+	xa_store_many_order(xa, index, order);
+	for (i = index; i < index + (1UL << order); i++)
+		xa_erase_index(xa, i);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_create_range_2(struct xarray *xa, unsigned order)
+{
+	unsigned long i;
+	unsigned long nr = 1UL << order;
+
+	for (i = 0; i < nr * nr; i += nr)
+		xa_store_many_order(xa, i, order);
+	for (i = 0; i < nr * nr; i++)
+		xa_erase_index(xa, i);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_create_range_3(void)
+{
+	XA_STATE(xas, NULL, 0);
+	xas_set_err(&xas, -EEXIST);
+	xas_create_range(&xas);
+	XA_BUG_ON(NULL, xas_error(&xas) != -EEXIST);
+}
+
+static noinline void check_create_range_4(struct xarray *xa,
+		unsigned long index, unsigned order)
+{
+	XA_STATE_ORDER(xas, xa, index, order);
+	unsigned long base = xas.xa_index;
+	unsigned long i = 0;
+
+	xa_store_index(xa, index, GFP_KERNEL);
+	do {
+		xas_lock(&xas);
+		xas_create_range(&xas);
+		if (xas_error(&xas))
+			goto unlock;
+		for (i = 0; i < (1UL << order); i++) {
+			void *old = xas_store(&xas, xa_mk_index(base + i));
+			if (xas.xa_index == index)
+				XA_BUG_ON(xa, old != xa_mk_index(base + i));
+			else
+				XA_BUG_ON(xa, old != NULL);
+			xas_next(&xas);
+		}
+unlock:
+		xas_unlock(&xas);
+	} while (xas_nomem(&xas, GFP_KERNEL));
+
+	XA_BUG_ON(xa, xas_error(&xas));
+
+	for (i = base; i < base + (1UL << order); i++)
+		xa_erase_index(xa, i);
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_create_range_5(struct xarray *xa,
+		unsigned long index, unsigned int order)
+{
+	XA_STATE_ORDER(xas, xa, index, order);
+	unsigned int i;
+
+	xa_store_order(xa, index, order, xa_mk_index(index), GFP_KERNEL);
+
+	for (i = 0; i < order + 10; i++) {
+		do {
+			xas_lock(&xas);
+			xas_create_range(&xas);
+			xas_unlock(&xas);
+		} while (xas_nomem(&xas, GFP_KERNEL));
+	}
+
+	xa_destroy(xa);
+}
+
+static noinline void check_create_range(struct xarray *xa)
+{
+	unsigned int order;
+	unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 12 : 1;
+
+	for (order = 0; order < max_order; order++) {
+		check_create_range_1(xa, 0, order);
+		check_create_range_1(xa, 1U << order, order);
+		check_create_range_1(xa, 2U << order, order);
+		check_create_range_1(xa, 3U << order, order);
+		check_create_range_1(xa, 1U << 24, order);
+		if (order < 10)
+			check_create_range_2(xa, order);
+
+		check_create_range_4(xa, 0, order);
+		check_create_range_4(xa, 1U << order, order);
+		check_create_range_4(xa, 2U << order, order);
+		check_create_range_4(xa, 3U << order, order);
+		check_create_range_4(xa, 1U << 24, order);
+
+		check_create_range_4(xa, 1, order);
+		check_create_range_4(xa, (1U << order) + 1, order);
+		check_create_range_4(xa, (2U << order) + 1, order);
+		check_create_range_4(xa, (2U << order) - 1, order);
+		check_create_range_4(xa, (3U << order) + 1, order);
+		check_create_range_4(xa, (3U << order) - 1, order);
+		check_create_range_4(xa, (1U << 24) + 1, order);
+
+		check_create_range_5(xa, 0, order);
+		check_create_range_5(xa, (1U << order), order);
+	}
+
+	check_create_range_3();
+}
+
+static noinline void __check_store_range(struct xarray *xa, unsigned long first,
+		unsigned long last)
+{
+#ifdef CONFIG_XARRAY_MULTI
+	xa_store_range(xa, first, last, xa_mk_index(first), GFP_KERNEL);
+
+	XA_BUG_ON(xa, xa_load(xa, first) != xa_mk_index(first));
+	XA_BUG_ON(xa, xa_load(xa, last) != xa_mk_index(first));
+	XA_BUG_ON(xa, xa_load(xa, first - 1) != NULL);
+	XA_BUG_ON(xa, xa_load(xa, last + 1) != NULL);
+
+	xa_store_range(xa, first, last, NULL, GFP_KERNEL);
+#endif
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_store_range(struct xarray *xa)
+{
+	unsigned long i, j;
+
+	for (i = 0; i < 128; i++) {
+		for (j = i; j < 128; j++) {
+			__check_store_range(xa, i, j);
+			__check_store_range(xa, 128 + i, 128 + j);
+			__check_store_range(xa, 4095 + i, 4095 + j);
+			__check_store_range(xa, 4096 + i, 4096 + j);
+			__check_store_range(xa, 123456 + i, 123456 + j);
+			__check_store_range(xa, (1 << 24) + i, (1 << 24) + j);
+		}
+	}
+}
+
+#ifdef CONFIG_XARRAY_MULTI
+static void check_split_1(struct xarray *xa, unsigned long index,
+				unsigned int order, unsigned int new_order)
+{
+	XA_STATE_ORDER(xas, xa, index, new_order);
+	unsigned int i, found;
+	void *entry;
+
+	xa_store_order(xa, index, order, xa, GFP_KERNEL);
+	xa_set_mark(xa, index, XA_MARK_1);
+
+	xas_split_alloc(&xas, xa, order, GFP_KERNEL);
+	xas_lock(&xas);
+	xas_split(&xas, xa, order);
+	for (i = 0; i < (1 << order); i += (1 << new_order))
+		__xa_store(xa, index + i, xa_mk_index(index + i), 0);
+	xas_unlock(&xas);
+
+	for (i = 0; i < (1 << order); i++) {
+		unsigned int val = index + (i & ~((1 << new_order) - 1));
+		XA_BUG_ON(xa, xa_load(xa, index + i) != xa_mk_index(val));
+	}
+
+	xa_set_mark(xa, index, XA_MARK_0);
+	XA_BUG_ON(xa, !xa_get_mark(xa, index, XA_MARK_0));
+
+	xas_set_order(&xas, index, 0);
+	found = 0;
+	rcu_read_lock();
+	xas_for_each_marked(&xas, entry, ULONG_MAX, XA_MARK_1) {
+		found++;
+		XA_BUG_ON(xa, xa_is_internal(entry));
+	}
+	rcu_read_unlock();
+	XA_BUG_ON(xa, found != 1 << (order - new_order));
+
+	xa_destroy(xa);
+}
+
+static void check_split_2(struct xarray *xa, unsigned long index,
+				unsigned int order, unsigned int new_order)
+{
+	XA_STATE_ORDER(xas, xa, index, new_order);
+	unsigned int i, found;
+	void *entry;
+
+	xa_store_order(xa, index, order, xa, GFP_KERNEL);
+	xa_set_mark(xa, index, XA_MARK_1);
+
+	/* allocate a node for xas_try_split() */
+	xas_set_err(&xas, -ENOMEM);
+	XA_BUG_ON(xa, !xas_nomem(&xas, GFP_KERNEL));
+
+	xas_lock(&xas);
+	xas_try_split(&xas, xa, order);
+	if (((new_order / XA_CHUNK_SHIFT) < (order / XA_CHUNK_SHIFT)) &&
+	    new_order < order - 1) {
+		XA_BUG_ON(xa, !xas_error(&xas) || xas_error(&xas) != -EINVAL);
+		xas_unlock(&xas);
+		goto out;
+	}
+	for (i = 0; i < (1 << order); i += (1 << new_order))
+		__xa_store(xa, index + i, xa_mk_index(index + i), 0);
+	xas_unlock(&xas);
+
+	for (i = 0; i < (1 << order); i++) {
+		unsigned int val = index + (i & ~((1 << new_order) - 1));
+		XA_BUG_ON(xa, xa_load(xa, index + i) != xa_mk_index(val));
+	}
+
+	xa_set_mark(xa, index, XA_MARK_0);
+	XA_BUG_ON(xa, !xa_get_mark(xa, index, XA_MARK_0));
+
+	xas_set_order(&xas, index, 0);
+	found = 0;
+	rcu_read_lock();
+	xas_for_each_marked(&xas, entry, ULONG_MAX, XA_MARK_1) {
+		found++;
+		XA_BUG_ON(xa, xa_is_internal(entry));
+	}
+	rcu_read_unlock();
+	XA_BUG_ON(xa, found != 1 << (order - new_order));
+out:
+	xas_destroy(&xas);
+	xa_destroy(xa);
+}
+
+static noinline void check_split(struct xarray *xa)
+{
+	unsigned int order, new_order;
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	for (order = 1; order < 2 * XA_CHUNK_SHIFT; order++) {
+		for (new_order = 0; new_order < order; new_order++) {
+			check_split_1(xa, 0, order, new_order);
+			check_split_1(xa, 1UL << order, order, new_order);
+			check_split_1(xa, 3UL << order, order, new_order);
+
+			check_split_2(xa, 0, order, new_order);
+			check_split_2(xa, 1UL << order, order, new_order);
+			check_split_2(xa, 3UL << order, order, new_order);
+		}
+	}
+}
+#else
+static void check_split(struct xarray *xa) { }
+#endif
+
+static void check_align_1(struct xarray *xa, char *name)
+{
+	int i;
+	unsigned int id;
+	unsigned long index;
+	void *entry;
+
+	for (i = 0; i < 8; i++) {
+		XA_BUG_ON(xa, xa_alloc(xa, &id, name + i, xa_limit_32b,
+					GFP_KERNEL) != 0);
+		XA_BUG_ON(xa, id != i);
+	}
+	xa_for_each(xa, index, entry)
+		XA_BUG_ON(xa, xa_is_err(entry));
+	xa_destroy(xa);
+}
+
+/*
+ * We should always be able to store without allocating memory after
+ * reserving a slot.
+ */
+static void check_align_2(struct xarray *xa, char *name)
+{
+	int i;
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	for (i = 0; i < 8; i++) {
+		XA_BUG_ON(xa, xa_store(xa, 0, name + i, GFP_KERNEL) != NULL);
+		xa_erase(xa, 0);
+	}
+
+	for (i = 0; i < 8; i++) {
+		XA_BUG_ON(xa, xa_reserve(xa, 0, GFP_KERNEL) != 0);
+		XA_BUG_ON(xa, xa_store(xa, 0, name + i, 0) != NULL);
+		xa_erase(xa, 0);
+	}
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+static noinline void check_align(struct xarray *xa)
+{
+	char name[] = "Motorola 68000";
+
+	check_align_1(xa, name);
+	check_align_1(xa, name + 1);
+	check_align_1(xa, name + 2);
+	check_align_1(xa, name + 3);
+	check_align_2(xa, name);
+}
+
+static LIST_HEAD(shadow_nodes);
+
+static void test_update_node(struct xa_node *node)
+{
+	if (node->count && node->count == node->nr_values) {
+		if (list_empty(&node->private_list))
+			list_add(&shadow_nodes, &node->private_list);
+	} else {
+		if (!list_empty(&node->private_list))
+			list_del_init(&node->private_list);
+	}
+}
+
+static noinline void shadow_remove(struct xarray *xa)
+{
+	struct xa_node *node;
+
+	xa_lock(xa);
+	while ((node = list_first_entry_or_null(&shadow_nodes,
+					struct xa_node, private_list))) {
+		XA_BUG_ON(xa, node->array != xa);
+		list_del_init(&node->private_list);
+		xa_delete_node(node, test_update_node);
+	}
+	xa_unlock(xa);
+}
+
+static noinline void check_workingset(struct xarray *xa, unsigned long index)
+{
+	XA_STATE(xas, xa, index);
+	xas_set_update(&xas, test_update_node);
+
+	do {
+		xas_lock(&xas);
+		xas_store(&xas, xa_mk_value(0));
+		xas_next(&xas);
+		xas_store(&xas, xa_mk_value(1));
+		xas_unlock(&xas);
+	} while (xas_nomem(&xas, GFP_KERNEL));
+
+	XA_BUG_ON(xa, list_empty(&shadow_nodes));
+
+	xas_lock(&xas);
+	xas_next(&xas);
+	xas_store(&xas, &xas);
+	XA_BUG_ON(xa, !list_empty(&shadow_nodes));
+
+	xas_store(&xas, xa_mk_value(2));
+	xas_unlock(&xas);
+	XA_BUG_ON(xa, list_empty(&shadow_nodes));
+
+	shadow_remove(xa);
+	XA_BUG_ON(xa, !list_empty(&shadow_nodes));
+	XA_BUG_ON(xa, !xa_empty(xa));
+}
+
+/*
+ * Check that the pointer / value / sibling entries are accounted the
+ * way we expect them to be.
+ */
+static noinline void check_account(struct xarray *xa)
+{
+#ifdef CONFIG_XARRAY_MULTI
+	unsigned int order;
+
+	for (order = 1; order < 12; order++) {
+		XA_STATE(xas, xa, 1 << order);
+
+		xa_store_order(xa, 0, order, xa, GFP_KERNEL);
+		rcu_read_lock();
+		xas_load(&xas);
+		XA_BUG_ON(xa, xas.xa_node->count == 0);
+		XA_BUG_ON(xa, xas.xa_node->count > (1 << order));
+		XA_BUG_ON(xa, xas.xa_node->nr_values != 0);
+		rcu_read_unlock();
+
+		xa_store_order(xa, 1 << order, order, xa_mk_index(1UL << order),
+				GFP_KERNEL);
+		XA_BUG_ON(xa, xas.xa_node->count != xas.xa_node->nr_values * 2);
+
+		xa_erase(xa, 1 << order);
+		XA_BUG_ON(xa, xas.xa_node->nr_values != 0);
+
+		xa_erase(xa, 0);
+		XA_BUG_ON(xa, !xa_empty(xa));
+	}
+#endif
+}
+
+static noinline void check_get_order(struct xarray *xa)
+{
+	unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 20 : 1;
+	unsigned int order;
+	unsigned long i, j;
+
+	for (i = 0; i < 3; i++)
+		XA_BUG_ON(xa, xa_get_order(xa, i) != 0);
+
+	for (order = 0; order < max_order; order++) {
+		for (i = 0; i < 10; i++) {
+			xa_store_order(xa, i << order, order,
+					xa_mk_index(i << order), GFP_KERNEL);
+			for (j = i << order; j < (i + 1) << order; j++)
+				XA_BUG_ON(xa, xa_get_order(xa, j) != order);
+			xa_erase(xa, i << order);
+		}
+	}
+}
+
+static noinline void check_xas_get_order(struct xarray *xa)
+{
+	XA_STATE(xas, xa, 0);
+
+	unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 20 : 1;
+	unsigned int order;
+	unsigned long i, j;
+
+	for (order = 0; order < max_order; order++) {
+		for (i = 0; i < 10; i++) {
+			xas_set_order(&xas, i << order, order);
+			do {
+				xas_lock(&xas);
+				xas_store(&xas, xa_mk_value(i));
+				xas_unlock(&xas);
+			} while (xas_nomem(&xas, GFP_KERNEL));
+
+			for (j = i << order; j < (i + 1) << order; j++) {
+				xas_set_order(&xas, j, 0);
+				rcu_read_lock();
+				xas_load(&xas);
+				XA_BUG_ON(xa, xas_get_order(&xas) != order);
+				rcu_read_unlock();
+			}
+
+			xas_lock(&xas);
+			xas_set_order(&xas, i << order, order);
+			xas_store(&xas, NULL);
+			xas_unlock(&xas);
+		}
+	}
+}
+
+static noinline void check_xas_conflict_get_order(struct xarray *xa)
+{
+	XA_STATE(xas, xa, 0);
+
+	void *entry;
+	int only_once;
+	unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 20 : 1;
+	unsigned int order;
+	unsigned long i, j, k;
+
+	for (order = 0; order < max_order; order++) {
+		for (i = 0; i < 10; i++) {
+			xas_set_order(&xas, i << order, order);
+			do {
+				xas_lock(&xas);
+				xas_store(&xas, xa_mk_value(i));
+				xas_unlock(&xas);
+			} while (xas_nomem(&xas, GFP_KERNEL));
+
+			/*
+			 * Ensure xas_get_order works with xas_for_each_conflict.
+			 */
+			j = i << order;
+			for (k = 0; k < order; k++) {
+				only_once = 0;
+				xas_set_order(&xas, j + (1 << k), k);
+				xas_lock(&xas);
+				xas_for_each_conflict(&xas, entry) {
+					XA_BUG_ON(xa, entry != xa_mk_value(i));
+					XA_BUG_ON(xa, xas_get_order(&xas) != order);
+					only_once++;
+				}
+				XA_BUG_ON(xa, only_once != 1);
+				xas_unlock(&xas);
+			}
+
+			if (order < max_order - 1) {
+				only_once = 0;
+				xas_set_order(&xas, (i & ~1UL) << order, order + 1);
+				xas_lock(&xas);
+				xas_for_each_conflict(&xas, entry) {
+					XA_BUG_ON(xa, entry != xa_mk_value(i));
+					XA_BUG_ON(xa, xas_get_order(&xas) != order);
+					only_once++;
+				}
+				XA_BUG_ON(xa, only_once != 1);
+				xas_unlock(&xas);
+			}
+
+			xas_set_order(&xas, i << order, order);
+			xas_lock(&xas);
+			xas_store(&xas, NULL);
+			xas_unlock(&xas);
+		}
+	}
+}
+
+
+static noinline void check_destroy(struct xarray *xa)
+{
+	unsigned long index;
+
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* Destroying an empty array is a no-op */
+	xa_destroy(xa);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+	/* Destroying an array with a single entry */
+	for (index = 0; index < 1000; index++) {
+		xa_store_index(xa, index, GFP_KERNEL);
+		XA_BUG_ON(xa, xa_empty(xa));
+		xa_destroy(xa);
+		XA_BUG_ON(xa, !xa_empty(xa));
+	}
+
+	/* Destroying an array with a single entry at ULONG_MAX */
+	xa_store(xa, ULONG_MAX, xa, GFP_KERNEL);
+	XA_BUG_ON(xa, xa_empty(xa));
+	xa_destroy(xa);
+	XA_BUG_ON(xa, !xa_empty(xa));
+
+#ifdef CONFIG_XARRAY_MULTI
+	/* Destroying an array with a multi-index entry */
+	xa_store_order(xa, 1 << 11, 11, xa, GFP_KERNEL);
+	XA_BUG_ON(xa, xa_empty(xa));
+	xa_destroy(xa);
+	XA_BUG_ON(xa, !xa_empty(xa));
+#endif
+}
+
+static DEFINE_XARRAY(array);
+
+static int xarray_checks(void)
+{
+	check_xa_err(&array);
+	check_xas_retry(&array);
+	check_xa_load(&array);
+	check_xa_mark(&array);
+	check_xa_shrink(&array);
+	check_xas_erase(&array);
+	check_insert(&array);
+	check_cmpxchg(&array);
+	check_cmpxchg_order(&array);
+	check_reserve(&array);
+	check_reserve(&xa0);
+	check_multi_store(&array);
+	check_multi_store_advanced(&array);
+	check_get_order(&array);
+	check_xas_get_order(&array);
+	check_xas_conflict_get_order(&array);
+	check_xa_alloc();
+	check_find(&array);
+	check_find_entry(&array);
+	check_pause(&array);
+	check_account(&array);
+	check_destroy(&array);
+	check_move(&array);
+	check_create_range(&array);
+	check_store_range(&array);
+	check_store_iter(&array);
+	check_align(&xa0);
+	check_split(&array);
+
+	check_workingset(&array, 0);
+	check_workingset(&array, 64);
+	check_workingset(&array, 4096);
+
+	printk("XArray: %u of %u tests passed\n", tests_passed, tests_run);
+	return (tests_run == tests_passed) ? 0 : -EINVAL;
+}
+
+static void xarray_exit(void)
+{
+}
+
+module_init(xarray_checks);
+module_exit(xarray_exit);
+MODULE_AUTHOR("Matthew Wilcox <willy@infradead.org>");
+MODULE_DESCRIPTION("XArray API test module");
+MODULE_LICENSE("GPL");