memblock tests: add additional tests for basic api and memblock_alloc

Add tests for memblock_add(), memblock_reserve(), memblock_remove(),
memblock_free(), and memblock_alloc() for the following test scenarios.

memblock_add() and memblock_reserve():
- add/reserve a memory block in the gap between two existing memory
  blocks, and check that the blocks are merged into one region
- try to add/reserve memblock regions that extend past PHYS_ADDR_MAX

memblock_remove() and memblock_free():
- remove/free a region when it is the only available region
    + These tests ensure that the first region is overwritten with a
      "dummy" region when the last remaining region of that type is
      removed or freed.
- remove/free() a region that overlaps with two existing regions of the
  relevant type
- try to remove/free memblock regions that extend past PHYS_ADDR_MAX

memblock_alloc():
- try to allocate a region that is larger than the total size of available
  memory (memblock.memory)

Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Shaoqin Huang <shaoqin.huang@intel.com>
Signed-off-by: Rebecca Mckeever <remckee0@gmail.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Link: https://lore.kernel.org/r/c23c0393c5b9a53fe7f676996913c629495e9727.1661578349.git.remckee0@gmail.com

tools/testing/memblock/tests/alloc_api.c

@@ -469,6 +469,40 @@ static int alloc_no_memory_generic_check(void)
 	return 0;
 }
 
+/*
+ * A test that tries to allocate a region that is larger than the total size of
+ * available memory (memblock.memory):
+ *
+ *  +-----------------------------------+
+ *  |                 new               |
+ *  +-----------------------------------+
+ *  |                                 |
+ *  |                                 |
+ *  +---------------------------------+
+ *
+ * Expect no allocation to happen.
+ */
+static int alloc_too_large_generic_check(void)
+{
+	struct memblock_region *rgn = &memblock.reserved.regions[0];
+	void *allocated_ptr = NULL;
+
+	PREFIX_PUSH();
+
+	setup_memblock();
+
+	allocated_ptr = memblock_alloc(MEM_SIZE + SZ_2, SMP_CACHE_BYTES);
+
+	ASSERT_EQ(allocated_ptr, NULL);
+	ASSERT_EQ(rgn->size, 0);
+	ASSERT_EQ(rgn->base, 0);
+	ASSERT_EQ(memblock.reserved.total_size, 0);
+
+	test_pass_pop();
+
+	return 0;
+}
+
 /*
  * A simple test that tries to allocate a small memory region.
  * Expect to allocate an aligned region at the beginning of the available
@@ -813,6 +847,15 @@ static int alloc_no_memory_check(void)
 	return 0;
 }
 
+static int alloc_too_large_check(void)
+{
+	test_print("\tRunning %s...\n", __func__);
+	run_top_down(alloc_too_large_generic_check);
+	run_bottom_up(alloc_too_large_generic_check);
+
+	return 0;
+}
+
 int memblock_alloc_checks(void)
 {
 	const char *func_testing = "memblock_alloc";
@@ -835,6 +878,7 @@ int memblock_alloc_checks(void)
 	alloc_no_space_check();
 	alloc_limited_space_check();
 	alloc_no_memory_check();
+	alloc_too_large_check();
 
 	dummy_physical_memory_cleanup();
 

tools/testing/memblock/tests/basic_api.c

@@ -326,6 +326,102 @@ static int memblock_add_twice_check(void)
 	return 0;
 }
 
+/*
+ * A test that tries to add two memory blocks that don't overlap with one
+ * another and then add a third memory block in the space between the first two:
+ *
+ *  |        +--------+--------+--------+  |
+ *  |        |   r1   |   r3   |   r2   |  |
+ *  +--------+--------+--------+--------+--+
+ *
+ * Expect to merge the three entries into one region that starts at r1.base
+ * and has size of r1.size + r2.size + r3.size. The region counter and total
+ * size of the available memory are updated.
+ */
+static int memblock_add_between_check(void)
+{
+	struct memblock_region *rgn;
+	phys_addr_t total_size;
+
+	rgn = &memblock.memory.regions[0];
+
+	struct region r1 = {
+		.base = SZ_1G,
+		.size = SZ_8K
+	};
+	struct region r2 = {
+		.base = SZ_1G + SZ_16K,
+		.size = SZ_8K
+	};
+	struct region r3 = {
+		.base = SZ_1G + SZ_8K,
+		.size = SZ_8K
+	};
+
+	PREFIX_PUSH();
+
+	total_size = r1.size + r2.size + r3.size;
+
+	reset_memblock_regions();
+	memblock_add(r1.base, r1.size);
+	memblock_add(r2.base, r2.size);
+	memblock_add(r3.base, r3.size);
+
+	ASSERT_EQ(rgn->base, r1.base);
+	ASSERT_EQ(rgn->size, total_size);
+
+	ASSERT_EQ(memblock.memory.cnt, 1);
+	ASSERT_EQ(memblock.memory.total_size, total_size);
+
+	test_pass_pop();
+
+	return 0;
+}
+
+/*
+ * A simple test that tries to add a memory block r when r extends past
+ * PHYS_ADDR_MAX:
+ *
+ *                               +--------+
+ *                               |    r   |
+ *                               +--------+
+ *  |                            +----+
+ *  |                            | rgn|
+ *  +----------------------------+----+
+ *
+ * Expect to add a memory block of size PHYS_ADDR_MAX - r.base. Expect the
+ * total size of available memory and the counter to be updated.
+ */
+static int memblock_add_near_max_check(void)
+{
+	struct memblock_region *rgn;
+	phys_addr_t total_size;
+
+	rgn = &memblock.memory.regions[0];
+
+	struct region r = {
+		.base = PHYS_ADDR_MAX - SZ_1M,
+		.size = SZ_2M
+	};
+
+	PREFIX_PUSH();
+
+	total_size = PHYS_ADDR_MAX - r.base;
+
+	reset_memblock_regions();
+	memblock_add(r.base, r.size);
+
+	ASSERT_EQ(rgn->base, r.base);
+	ASSERT_EQ(rgn->size, total_size);
+
+	ASSERT_EQ(memblock.memory.cnt, 1);
+	ASSERT_EQ(memblock.memory.total_size, total_size);
+
+	test_pass_pop();
+
+	return 0;
+}
+
 static int memblock_add_checks(void)
 {
 	prefix_reset();
@@ -339,6 +435,8 @@ static int memblock_add_checks(void)
 	memblock_add_overlap_bottom_check();
 	memblock_add_within_check();
 	memblock_add_twice_check();
+	memblock_add_between_check();
+	memblock_add_near_max_check();
 
 	prefix_pop();
 
@@ -604,6 +702,102 @@ static int memblock_reserve_twice_check(void)
 	return 0;
 }
 
+/*
+ * A test that tries to mark two memory blocks that don't overlap as reserved
+ * and then reserve a third memory block in the space between the first two:
+ *
+ *  |        +--------+--------+--------+  |
+ *  |        |   r1   |   r3   |   r2   |  |
+ *  +--------+--------+--------+--------+--+
+ *
+ * Expect to merge the three entries into one reserved region that starts at
+ * r1.base and has size of r1.size + r2.size + r3.size. The region counter and
+ * total for memblock.reserved are updated.
+ */
+static int memblock_reserve_between_check(void)
+{
+	struct memblock_region *rgn;
+	phys_addr_t total_size;
+
+	rgn = &memblock.reserved.regions[0];
+
+	struct region r1 = {
+		.base = SZ_1G,
+		.size = SZ_8K
+	};
+	struct region r2 = {
+		.base = SZ_1G + SZ_16K,
+		.size = SZ_8K
+	};
+	struct region r3 = {
+		.base = SZ_1G + SZ_8K,
+		.size = SZ_8K
+	};
+
+	PREFIX_PUSH();
+
+	total_size = r1.size + r2.size + r3.size;
+
+	reset_memblock_regions();
+	memblock_reserve(r1.base, r1.size);
+	memblock_reserve(r2.base, r2.size);
+	memblock_reserve(r3.base, r3.size);
+
+	ASSERT_EQ(rgn->base, r1.base);
+	ASSERT_EQ(rgn->size, total_size);
+
+	ASSERT_EQ(memblock.reserved.cnt, 1);
+	ASSERT_EQ(memblock.reserved.total_size, total_size);
+
+	test_pass_pop();
+
+	return 0;
+}
+
+/*
+ * A simple test that tries to reserve a memory block r when r extends past
+ * PHYS_ADDR_MAX:
+ *
+ *                               +--------+
+ *                               |    r   |
+ *                               +--------+
+ *  |                            +----+
+ *  |                            | rgn|
+ *  +----------------------------+----+
+ *
+ * Expect to reserve a memory block of size PHYS_ADDR_MAX - r.base. Expect the
+ * total size of reserved memory and the counter to be updated.
+ */
+static int memblock_reserve_near_max_check(void)
+{
+	struct memblock_region *rgn;
+	phys_addr_t total_size;
+
+	rgn = &memblock.reserved.regions[0];
+
+	struct region r = {
+		.base = PHYS_ADDR_MAX - SZ_1M,
+		.size = SZ_2M
+	};
+
+	PREFIX_PUSH();
+
+	total_size = PHYS_ADDR_MAX - r.base;
+
+	reset_memblock_regions();
+	memblock_reserve(r.base, r.size);
+
+	ASSERT_EQ(rgn->base, r.base);
+	ASSERT_EQ(rgn->size, total_size);
+
+	ASSERT_EQ(memblock.reserved.cnt, 1);
+	ASSERT_EQ(memblock.reserved.total_size, total_size);
+
+	test_pass_pop();
+
+	return 0;
+}
+
 static int memblock_reserve_checks(void)
 {
 	prefix_reset();
@@ -616,6 +810,8 @@ static int memblock_reserve_checks(void)
 	memblock_reserve_overlap_bottom_check();
 	memblock_reserve_within_check();
 	memblock_reserve_twice_check();
+	memblock_reserve_between_check();
+	memblock_reserve_near_max_check();
 
 	prefix_pop();
 
@@ -887,6 +1083,155 @@ static int memblock_remove_within_check(void)
 	return 0;
 }
 
+/*
+ * A simple test that tries to remove a region r1 from the array of
+ * available memory regions when r1 is the only available region.
+ * Expect to add a memory block r1 and then remove r1 so that a dummy
+ * region is added. The region counter stays the same, and the total size
+ * is updated.
+ */
+static int memblock_remove_only_region_check(void)
+{
+	struct memblock_region *rgn;
+
+	rgn = &memblock.memory.regions[0];
+
+	struct region r1 = {
+		.base = SZ_2K,
+		.size = SZ_4K
+	};
+
+	PREFIX_PUSH();
+
+	reset_memblock_regions();
+	memblock_add(r1.base, r1.size);
+	memblock_remove(r1.base, r1.size);
+
+	ASSERT_EQ(rgn->base, 0);
+	ASSERT_EQ(rgn->size, 0);
+
+	ASSERT_EQ(memblock.memory.cnt, 1);
+	ASSERT_EQ(memblock.memory.total_size, 0);
+
+	test_pass_pop();
+
+	return 0;
+}
+
+/*
+ * A simple test that tries remove a region r2 from the array of available
+ * memory regions when r2 extends past PHYS_ADDR_MAX:
+ *
+ *                               +--------+
+ *                               |   r2   |
+ *                               +--------+
+ *  |                        +---+....+
+ *  |                        |rgn|    |
+ *  +------------------------+---+----+
+ *
+ * Expect that only the portion between PHYS_ADDR_MAX and r2.base is removed.
+ * Expect the total size of available memory to be updated and the counter to
+ * not be updated.
+ */
+static int memblock_remove_near_max_check(void)
+{
+	struct memblock_region *rgn;
+	phys_addr_t total_size;
+
+	rgn = &memblock.memory.regions[0];
+
+	struct region r1 = {
+		.base = PHYS_ADDR_MAX - SZ_2M,
+		.size = SZ_2M
+	};
+
+	struct region r2 = {
+		.base = PHYS_ADDR_MAX - SZ_1M,
+		.size = SZ_2M
+	};
+
+	PREFIX_PUSH();
+
+	total_size = r1.size - (PHYS_ADDR_MAX - r2.base);
+
+	reset_memblock_regions();
+	memblock_add(r1.base, r1.size);
+	memblock_remove(r2.base, r2.size);
+
+	ASSERT_EQ(rgn->base, r1.base);
+	ASSERT_EQ(rgn->size, total_size);
+
+	ASSERT_EQ(memblock.memory.cnt, 1);
+	ASSERT_EQ(memblock.memory.total_size, total_size);
+
+	test_pass_pop();
+
+	return 0;
+}
+
+/*
+ * A test that tries to remove a region r3 that overlaps with two existing
+ * regions r1 and r2:
+ *
+ *            +----------------+
+ *            |       r3       |
+ *            +----------------+
+ *  |    +----+.....   ........+--------+
+ *  |    |    |r1  :   :       |r2      |     |
+ *  +----+----+----+---+-------+--------+-----+
+ *
+ * Expect that only the intersections of r1 with r3 and r2 with r3 are removed
+ * from the available memory pool. Expect the total size of available memory to
+ * be updated and the counter to not be updated.
+ */
+static int memblock_remove_overlap_two_check(void)
+{
+	struct memblock_region *rgn1, *rgn2;
+	phys_addr_t new_r1_size, new_r2_size, r2_end, r3_end, total_size;
+
+	rgn1 = &memblock.memory.regions[0];
+	rgn2 = &memblock.memory.regions[1];
+
+	struct region r1 = {
+		.base = SZ_16M,
+		.size = SZ_32M
+	};
+	struct region r2 = {
+		.base = SZ_64M,
+		.size = SZ_64M
+	};
+	struct region r3 = {
+		.base = SZ_32M,
+		.size = SZ_64M
+	};
+
+	PREFIX_PUSH();
+
+	r2_end = r2.base + r2.size;
+	r3_end = r3.base + r3.size;
+	new_r1_size = r3.base - r1.base;
+	new_r2_size = r2_end - r3_end;
+	total_size = new_r1_size + new_r2_size;
+
+	reset_memblock_regions();
+	memblock_add(r1.base, r1.size);
+	memblock_add(r2.base, r2.size);
+	memblock_remove(r3.base, r3.size);
+
+	ASSERT_EQ(rgn1->base, r1.base);
+	ASSERT_EQ(rgn1->size, new_r1_size);
+
+	ASSERT_EQ(rgn2->base, r3_end);
+	ASSERT_EQ(rgn2->size, new_r2_size);
+
+	ASSERT_EQ(memblock.memory.cnt, 2);
+	ASSERT_EQ(memblock.memory.total_size, total_size);
+
+	test_pass_pop();
+
+	return 0;
+}
+
 static int memblock_remove_checks(void)
 {
 	prefix_reset();
@@ -898,6 +1243,9 @@ static int memblock_remove_checks(void)
 	memblock_remove_overlap_top_check();
 	memblock_remove_overlap_bottom_check();
 	memblock_remove_within_check();
+	memblock_remove_only_region_check();
+	memblock_remove_near_max_check();
+	memblock_remove_overlap_two_check();
 
 	prefix_pop();
 
@@ -1163,6 +1511,154 @@ static int memblock_free_within_check(void)
 	return 0;
 }
 
+/*
+ * A simple test that tries to free a memory block r1 that was marked
+ * earlier as reserved when r1 is the only available region.
+ * Expect to reserve a memory block r1 and then free r1 so that r1 is
+ * overwritten with a dummy region. The region counter stays the same,
+ * and the total size is updated.
+ */
+static int memblock_free_only_region_check(void)
+{
+	struct memblock_region *rgn;
+
+	rgn = &memblock.reserved.regions[0];
+
+	struct region r1 = {
+		.base = SZ_2K,
+		.size = SZ_4K
+	};
+
+	PREFIX_PUSH();
+
+	reset_memblock_regions();
+	memblock_reserve(r1.base, r1.size);
+	memblock_free((void *)r1.base, r1.size);
+
+	ASSERT_EQ(rgn->base, 0);
+	ASSERT_EQ(rgn->size, 0);
+
+	ASSERT_EQ(memblock.reserved.cnt, 1);
+	ASSERT_EQ(memblock.reserved.total_size, 0);
+
+	test_pass_pop();
+
+	return 0;
+}
+
+/*
+ * A simple test that tries free a region r2 when r2 extends past PHYS_ADDR_MAX:
+ *
+ *                               +--------+
+ *                               |   r2   |
+ *                               +--------+
+ *  |                        +---+....+
+ *  |                        |rgn|    |
+ *  +------------------------+---+----+
+ *
+ * Expect that only the portion between PHYS_ADDR_MAX and r2.base is freed.
+ * Expect the total size of reserved memory to be updated and the counter to
+ * not be updated.
+ */
+static int memblock_free_near_max_check(void)
+{
+	struct memblock_region *rgn;
+	phys_addr_t total_size;
+
+	rgn = &memblock.reserved.regions[0];
+
+	struct region r1 = {
+		.base = PHYS_ADDR_MAX - SZ_2M,
+		.size = SZ_2M
+	};
+
+	struct region r2 = {
+		.base = PHYS_ADDR_MAX - SZ_1M,
+		.size = SZ_2M
+	};
+
+	PREFIX_PUSH();
+
+	total_size = r1.size - (PHYS_ADDR_MAX - r2.base);
+
+	reset_memblock_regions();
+	memblock_reserve(r1.base, r1.size);
+	memblock_free((void *)r2.base, r2.size);
+
+	ASSERT_EQ(rgn->base, r1.base);
+	ASSERT_EQ(rgn->size, total_size);
+
+	ASSERT_EQ(memblock.reserved.cnt, 1);
+	ASSERT_EQ(memblock.reserved.total_size, total_size);
+
+	test_pass_pop();
+
+	return 0;
+}
+
+/*
+ * A test that tries to free a reserved region r3 that overlaps with two
+ * existing reserved regions r1 and r2:
+ *
+ *            +----------------+
+ *            |       r3       |
+ *            +----------------+
+ *  |    +----+.....   ........+--------+
+ *  |    |    |r1  :   :       |r2      |     |
+ *  +----+----+----+---+-------+--------+-----+
+ *
+ * Expect that only the intersections of r1 with r3 and r2 with r3 are freed
+ * from the collection of reserved memory. Expect the total size of reserved
+ * memory to be updated and the counter to not be updated.
+ */
+static int memblock_free_overlap_two_check(void)
+{
+	struct memblock_region *rgn1, *rgn2;
+	phys_addr_t new_r1_size, new_r2_size, r2_end, r3_end, total_size;
+
+	rgn1 = &memblock.reserved.regions[0];
+	rgn2 = &memblock.reserved.regions[1];
+
+	struct region r1 = {
+		.base = SZ_16M,
+		.size = SZ_32M
+	};
+	struct region r2 = {
+		.base = SZ_64M,
+		.size = SZ_64M
+	};
+	struct region r3 = {
+		.base = SZ_32M,
+		.size = SZ_64M
+	};
+
+	PREFIX_PUSH();
+
+	r2_end = r2.base + r2.size;
+	r3_end = r3.base + r3.size;
+	new_r1_size = r3.base - r1.base;
+	new_r2_size = r2_end - r3_end;
+	total_size = new_r1_size + new_r2_size;
+
+	reset_memblock_regions();
+	memblock_reserve(r1.base, r1.size);
+	memblock_reserve(r2.base, r2.size);
+	memblock_free((void *)r3.base, r3.size);
+
+	ASSERT_EQ(rgn1->base, r1.base);
+	ASSERT_EQ(rgn1->size, new_r1_size);
+
+	ASSERT_EQ(rgn2->base, r3_end);
+	ASSERT_EQ(rgn2->size, new_r2_size);
+
+	ASSERT_EQ(memblock.reserved.cnt, 2);
+	ASSERT_EQ(memblock.reserved.total_size, total_size);
+
+	test_pass_pop();
+
+	return 0;
+}
+
 static int memblock_free_checks(void)
 {
 	prefix_reset();
@@ -1174,6 +1670,9 @@ static int memblock_free_checks(void)
 	memblock_free_overlap_top_check();
 	memblock_free_overlap_bottom_check();
 	memblock_free_within_check();
+	memblock_free_only_region_check();
+	memblock_free_near_max_check();
+	memblock_free_overlap_two_check();
 
 	prefix_pop();