memblock tests: Add memblock reset function

Memblock simulator needs to be able to reset memblock data structures
between different test cases. Add a function that sets all fields to
their default values.

Add a test checking if memblock is being initialized to expected values.
Signed-off-by: Karolina Drobnik <karolinadrobnik@gmail.com>
Signed-off-by: Mike Rapoport <rppt@kernel.org>
Link: https://lore.kernel.org/r/8c185aa7e0dd68c2c7e937c9a06c90ae413e240f.1643796665.git.karolinadrobnik@gmail.com

tools/testing/memblock/Makefile

@@ -6,7 +6,9 @@ CFLAGS += -I. -I../../include -Wall -O2 -fsanitize=address \
 	  -fsanitize=undefined -D CONFIG_PHYS_ADDR_T_64BIT
 LDFLAGS += -fsanitize=address -fsanitize=undefined
 TARGETS = main
-OFILES = main.o memblock.o lib/slab.o mmzone.o slab.o
+TEST_OFILES = tests/basic_api.o tests/common.o
+DEP_OFILES = memblock.o lib/slab.o mmzone.o slab.o
+OFILES = main.o $(DEP_OFILES) $(TEST_OFILES)
 EXTR_SRC = ../../../mm/memblock.c
 
 ifeq ($(BUILD), 32)

tools/testing/memblock/main.c

 // SPDX-License-Identifier: GPL-2.0-or-later
+#include "tests/basic_api.h"
 
 int main(int argc, char **argv)
 {
+	memblock_basic_checks();
 	return 0;
 }

tools/testing/memblock/tests/basic_api.c

+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <string.h>
+#include <linux/memblock.h>
+#include "basic_api.h"
+
+#define EXPECTED_MEMBLOCK_REGIONS			128
+
+static int memblock_initialization_check(void)
+{
+	reset_memblock();
+
+	assert(memblock.memory.regions);
+	assert(memblock.memory.cnt == 1);
+	assert(memblock.memory.max == EXPECTED_MEMBLOCK_REGIONS);
+	assert(strcmp(memblock.memory.name, "memory") == 0);
+
+	assert(memblock.reserved.regions);
+	assert(memblock.reserved.cnt == 1);
+	assert(memblock.memory.max == EXPECTED_MEMBLOCK_REGIONS);
+	assert(strcmp(memblock.reserved.name, "reserved") == 0);
+
+	assert(!memblock.bottom_up);
+	assert(memblock.current_limit == MEMBLOCK_ALLOC_ANYWHERE);
+
+	return 0;
+}
+
+int memblock_basic_checks(void)
+{
+	memblock_initialization_check();
+	return 0;
+}

tools/testing/memblock/tests/basic_api.h

+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _MEMBLOCK_BASIC_H
+#define _MEMBLOCK_BASIC_H
+
+#include <assert.h>
+#include "common.h"
+
+int memblock_basic_checks(void);
+
+#endif

tools/testing/memblock/tests/common.c

+// SPDX-License-Identifier: GPL-2.0-or-later
+#include "tests/common.h"
+#include <string.h>
+
+#define INIT_MEMBLOCK_REGIONS			128
+#define INIT_MEMBLOCK_RESERVED_REGIONS		INIT_MEMBLOCK_REGIONS
+
+void reset_memblock(void)
+{
+	memset(memblock.memory.regions, 0,
+	       memblock.memory.cnt * sizeof(struct memblock_region));
+	memset(memblock.reserved.regions, 0,
+	       memblock.reserved.cnt * sizeof(struct memblock_region));
+
+	memblock.memory.cnt	= 1;
+	memblock.memory.max	= INIT_MEMBLOCK_REGIONS;
+	memblock.memory.name	= "memory";
+	memblock.memory.total_size = 0;
+
+	memblock.reserved.cnt	= 1;
+	memblock.reserved.max	= INIT_MEMBLOCK_RESERVED_REGIONS;
+	memblock.reserved.name	= "reserved";
+	memblock.reserved.total_size = 0;
+
+	memblock.bottom_up	= false;
+	memblock.current_limit	= MEMBLOCK_ALLOC_ANYWHERE;
+}

tools/testing/memblock/tests/common.h

+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _MEMBLOCK_TEST_H
+#define _MEMBLOCK_TEST_H
+
+#include <linux/types.h>
+#include <linux/memblock.h>
+
+struct region {
+	phys_addr_t base;
+	phys_addr_t size;
+};
+
+void reset_memblock(void);
+
+#endif