// SPDX-License-Identifier: GPL-2.0
/*
* KUnit test suite for GEM objects backed by shmem buffers
*
* Copyright (C) 2023 Red Hat, Inc.
*
* Author: Marco Pagani <[email protected]>
*/
#include <linux/dma-buf.h>
#include <linux/iosys-map.h>
#include <linux/sizes.h>
#include <kunit/test.h>
#include <drm/drm_device.h>
#include <drm/drm_drv.h>
#include <drm/drm_gem.h>
#include <drm/drm_gem_shmem_helper.h>
#include <drm/drm_kunit_helpers.h>
#define TEST_SIZE SZ_1M
#define TEST_BYTE 0xae
/*
* Wrappers to avoid cast warnings when passing action functions
* directly to kunit_add_action().
*/
KUNIT_DEFINE_ACTION_WRAPPER(kfree_wrapper, kfree, const void *);
KUNIT_DEFINE_ACTION_WRAPPER(sg_free_table_wrapper, sg_free_table,
struct sg_table *);
KUNIT_DEFINE_ACTION_WRAPPER(drm_gem_shmem_free_wrapper, drm_gem_shmem_free,
struct drm_gem_shmem_object *);
/*
* Test creating a shmem GEM object backed by shmem buffer. The test
* case succeeds if the GEM object is successfully allocated with the
* shmem file node and object functions attributes set, and the size
* attribute is equal to the correct size.
*/
static void drm_gem_shmem_test_obj_create(struct kunit *test)
{
struct drm_device *drm_dev = test->priv;
struct drm_gem_shmem_object *shmem;
shmem = drm_gem_shmem_create(drm_dev, TEST_SIZE);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, shmem);
KUNIT_EXPECT_EQ(test, shmem->base.size, TEST_SIZE);
KUNIT_EXPECT_NOT_NULL(test, shmem->base.filp);
KUNIT_EXPECT_NOT_NULL(test, shmem->base.funcs);
drm_gem_shmem_free(shmem);
}
/*
* Test creating a shmem GEM object from a scatter/gather table exported
* via a DMA-BUF. The test case succeed if the GEM object is successfully
* created with the shmem file node attribute equal to NULL and the sgt
* attribute pointing to the scatter/gather table that has been imported.
*/
static void drm_gem_shmem_test_obj_create_private(struct kunit *test)
{
struct drm_device *drm_dev = test->priv;
struct drm_gem_shmem_object *shmem;
struct drm_gem_object *gem_obj;
struct dma_buf buf_mock;
struct dma_buf_attachment attach_mock;
struct sg_table *sgt;
char *buf;
int ret;
/* Create a mock scatter/gather table */
buf = kunit_kzalloc(test, TEST_SIZE, GFP_KERNEL);
KUNIT_ASSERT_NOT_NULL(test, buf);
sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
KUNIT_ASSERT_NOT_NULL(test, sgt);
ret = kunit_add_action_or_reset(test, kfree_wrapper, sgt);
KUNIT_ASSERT_EQ(test, ret, 0);
ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
KUNIT_ASSERT_EQ(test, ret, 0);
ret = kunit_add_action_or_reset(test, sg_free_table_wrapper, sgt);
KUNIT_ASSERT_EQ(test, ret, 0);
sg_init_one(sgt->sgl, buf, TEST_SIZE);
/*
* Set the DMA mask to 64-bits and map the sgtables
* otherwise drm_gem_shmem_free will cause a warning
* on debug kernels.
*/
ret = dma_set_mask(drm_dev->dev, DMA_BIT_MASK(64));
KUNIT_ASSERT_EQ(test, ret, 0);
ret = dma_map_sgtable(drm_dev->dev, sgt, DMA_BIDIRECTIONAL, 0);
KUNIT_ASSERT_EQ(test, ret, 0);
/* Init a mock DMA-BUF */
buf_mock.size = TEST_SIZE;
attach_mock.dmabuf = &buf_mock;
gem_obj = drm_gem_shmem_prime_import_sg_table(drm_dev, &attach_mock, sgt);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, gem_obj);
KUNIT_EXPECT_EQ(test, gem_obj->size, TEST_SIZE);
KUNIT_EXPECT_NULL(test, gem_obj->filp);
KUNIT_EXPECT_NOT_NULL(test, gem_obj->funcs);
/* The scatter/gather table will be freed by drm_gem_shmem_free */
kunit_remove_action(test, sg_free_table_wrapper, sgt);
kunit_remove_action(test, kfree_wrapper, sgt);
shmem = to_drm_gem_shmem_obj(gem_obj);
KUNIT_EXPECT_PTR_EQ(test, shmem->sgt, sgt);
drm_gem_shmem_free(shmem);
}
/*
* Test pinning backing pages for a shmem GEM object. The test case
* succeeds if a suitable number of backing pages are allocated, and
* the pages table counter attribute is increased by one.
*/
static void drm_gem_shmem_test_pin_pages(struct kunit *test)
{
struct drm_device *drm_dev = test->priv;
struct drm_gem_shmem_object *shmem;
int i, ret;
shmem = drm_gem_shmem_create(drm_dev, TEST_SIZE);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, shmem);
KUNIT_EXPECT_NULL(test, shmem->pages);
KUNIT_EXPECT_EQ(test, shmem->pages_use_count, 0);
ret = kunit_add_action_or_reset(test, drm_gem_shmem_free_wrapper, shmem);
KUNIT_ASSERT_EQ(test, ret, 0);
ret = drm_gem_shmem_pin(shmem);
KUNIT_ASSERT_EQ(test, ret, 0);
KUNIT_ASSERT_NOT_NULL(test, shmem->pages);
KUNIT_EXPECT_EQ(test, shmem->pages_use_count, 1);
for (i = 0; i < (shmem->base.size >> PAGE_SHIFT); i++)
KUNIT_ASSERT_NOT_NULL(test, shmem->pages[i]);
drm_gem_shmem_unpin(shmem);
KUNIT_EXPECT_NULL(test, shmem->pages);
KUNIT_EXPECT_EQ(test, shmem->pages_use_count, 0);
}
/*
* Test creating a virtual mapping for a shmem GEM object. The test
* case succeeds if the backing memory is mapped and the reference
* counter for virtual mapping is increased by one. Moreover, the test
* case writes and then reads a test pattern over the mapped memory.
*/
static void drm_gem_shmem_test_vmap(struct kunit *test)
{
struct drm_device *drm_dev = test->priv;
struct drm_gem_shmem_object *shmem;
struct iosys_map map;
int ret, i;
shmem = drm_gem_shmem_create(drm_dev, TEST_SIZE);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, shmem);
KUNIT_EXPECT_NULL(test, shmem->vaddr);
KUNIT_EXPECT_EQ(test, shmem->vmap_use_count, 0);
ret = kunit_add_action_or_reset(test, drm_gem_shmem_free_wrapper, shmem);
KUNIT_ASSERT_EQ(test, ret, 0);
ret = drm_gem_shmem_vmap(shmem, &map);
KUNIT_ASSERT_EQ(test, ret, 0);
KUNIT_ASSERT_NOT_NULL(test, shmem->vaddr);
KUNIT_ASSERT_FALSE(test, iosys_map_is_null(&map));
KUNIT_EXPECT_EQ(test, shmem->vmap_use_count, 1);
iosys_map_memset(&map, 0, TEST_BYTE, TEST_SIZE);
for (i = 0; i < TEST_SIZE; i++)
KUNIT_EXPECT_EQ(test, iosys_map_rd(&map, i, u8), TEST_BYTE);
drm_gem_shmem_vunmap(shmem, &map);
KUNIT_EXPECT_NULL(test, shmem->vaddr);
KUNIT_EXPECT_EQ(test, shmem->vmap_use_count, 0);
}
/*
* Test exporting a scatter/gather table of pinned pages suitable for
* PRIME usage from a shmem GEM object. The test case succeeds if a
* scatter/gather table large enough to accommodate the backing memory
* is successfully exported.
*/
static void drm_gem_shmem_test_get_pages_sgt(struct kunit *test)
{
struct drm_device *drm_dev = test->priv;
struct drm_gem_shmem_object *shmem;
struct sg_table *sgt;
struct scatterlist *sg;
unsigned int si, len = 0;
int ret;
shmem = drm_gem_shmem_create(drm_dev, TEST_SIZE);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, shmem);
ret = kunit_add_action_or_reset(test, drm_gem_shmem_free_wrapper, shmem);
KUNIT_ASSERT_EQ(test, ret, 0);
ret = drm_gem_shmem_pin(shmem);
KUNIT_ASSERT_EQ(test, ret, 0);
sgt = drm_gem_shmem_get_sg_table(shmem);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sgt);
KUNIT_EXPECT_NULL(test, shmem->sgt);
ret = kunit_add_action_or_reset(test, sg_free_table_wrapper, sgt);
KUNIT_ASSERT_EQ(test, ret, 0);
for_each_sgtable_sg(sgt, sg, si) {
KUNIT_EXPECT_NOT_NULL(test, sg);
len += sg->length;
}
KUNIT_EXPECT_GE(test, len, TEST_SIZE);
}
/*
* Test pinning pages and exporting a scatter/gather table suitable for
* driver usage from a shmem GEM object. The test case succeeds if the
* backing pages are pinned and a scatter/gather table large enough to
* accommodate the backing memory is successfully exported.
*/
static void drm_gem_shmem_test_get_sg_table(struct kunit *test)
{
struct drm_device *drm_dev = test->priv;
struct drm_gem_shmem_object *shmem;
struct sg_table *sgt;
struct scatterlist *sg;
unsigned int si, ret, len = 0;
shmem = drm_gem_shmem_create(drm_dev, TEST_SIZE);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, shmem);
ret = kunit_add_action_or_reset(test, drm_gem_shmem_free_wrapper, shmem);
KUNIT_ASSERT_EQ(test, ret, 0);
/* The scatter/gather table will be freed by drm_gem_shmem_free */
sgt = drm_gem_shmem_get_pages_sgt(shmem);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sgt);
KUNIT_ASSERT_NOT_NULL(test, shmem->pages);
KUNIT_EXPECT_EQ(test, shmem->pages_use_count, 1);
KUNIT_EXPECT_PTR_EQ(test, sgt, shmem->sgt);
for_each_sgtable_sg(sgt, sg, si) {
KUNIT_EXPECT_NOT_NULL(test, sg);
len += sg->length;
}
KUNIT_EXPECT_GE(test, len, TEST_SIZE);
}
/*
* Test updating the madvise state of a shmem GEM object. The test
* case checks that the function for setting madv updates it only if
* its current value is greater or equal than zero and returns false
* if it has a negative value.
*/
static void drm_gem_shmem_test_madvise(struct kunit *test)
{
struct drm_device *drm_dev = test->priv;
struct drm_gem_shmem_object *shmem;
int ret;
shmem = drm_gem_shmem_create(drm_dev, TEST_SIZE);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, shmem);
KUNIT_ASSERT_EQ(test, shmem->madv, 0);
ret = kunit_add_action_or_reset(test, drm_gem_shmem_free_wrapper, shmem);
KUNIT_ASSERT_EQ(test, ret, 0);
ret = drm_gem_shmem_madvise(shmem, 1);
KUNIT_EXPECT_TRUE(test, ret);
KUNIT_ASSERT_EQ(test, shmem->madv, 1);
/* Set madv to a negative value */
ret = drm_gem_shmem_madvise(shmem, -1);
KUNIT_EXPECT_FALSE(test, ret);
KUNIT_ASSERT_EQ(test, shmem->madv, -1);
/* Check that madv cannot be set back to a positive value */
ret = drm_gem_shmem_madvise(shmem, 0);
KUNIT_EXPECT_FALSE(test, ret);
KUNIT_ASSERT_EQ(test, shmem->madv, -1);
}
/*
* Test purging a shmem GEM object. First, assert that a newly created
* shmem GEM object is not purgeable. Then, set madvise to a positive
* value and call drm_gem_shmem_get_pages_sgt() to pin and dma-map the
* backing pages. Finally, assert that the shmem GEM object is now
* purgeable and purge it.
*/
static void drm_gem_shmem_test_purge(struct kunit *test)
{
struct drm_device *drm_dev = test->priv;
struct drm_gem_shmem_object *shmem;
struct sg_table *sgt;
int ret;
shmem = drm_gem_shmem_create(drm_dev, TEST_SIZE);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, shmem);
ret = kunit_add_action_or_reset(test, drm_gem_shmem_free_wrapper, shmem);
KUNIT_ASSERT_EQ(test, ret, 0);
ret = drm_gem_shmem_is_purgeable(shmem);
KUNIT_EXPECT_FALSE(test, ret);
ret = drm_gem_shmem_madvise(shmem, 1);
KUNIT_EXPECT_TRUE(test, ret);
/* The scatter/gather table will be freed by drm_gem_shmem_free */
sgt = drm_gem_shmem_get_pages_sgt(shmem);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sgt);
ret = drm_gem_shmem_is_purgeable(shmem);
KUNIT_EXPECT_TRUE(test, ret);
drm_gem_shmem_purge(shmem);
KUNIT_EXPECT_NULL(test, shmem->pages);
KUNIT_EXPECT_NULL(test, shmem->sgt);
KUNIT_EXPECT_EQ(test, shmem->madv, -1);
}
static int drm_gem_shmem_test_init(struct kunit *test)
{
struct device *dev;
struct drm_device *drm_dev;
/* Allocate a parent device */
dev = drm_kunit_helper_alloc_device(test);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev);
/*
* The DRM core will automatically initialize the GEM core and create
* a DRM Memory Manager object which provides an address space pool
* for GEM objects allocation.
*/
drm_dev = __drm_kunit_helper_alloc_drm_device(test, dev, sizeof(*drm_dev),
0, DRIVER_GEM);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, drm_dev);
test->priv = drm_dev;
return 0;
}
static struct kunit_case drm_gem_shmem_test_cases[] = {
KUNIT_CASE(drm_gem_shmem_test_obj_create),
KUNIT_CASE(drm_gem_shmem_test_obj_create_private),
KUNIT_CASE(drm_gem_shmem_test_pin_pages),
KUNIT_CASE(drm_gem_shmem_test_vmap),
KUNIT_CASE(drm_gem_shmem_test_get_pages_sgt),
KUNIT_CASE(drm_gem_shmem_test_get_sg_table),
KUNIT_CASE(drm_gem_shmem_test_madvise),
KUNIT_CASE(drm_gem_shmem_test_purge),
{}
};
static struct kunit_suite drm_gem_shmem_suite = {
.name = "drm_gem_shmem",
.init = drm_gem_shmem_test_init,
.test_cases = drm_gem_shmem_test_cases
};
kunit_test_suite(drm_gem_shmem_suite);
MODULE_DESCRIPTION("KUnit test suite for GEM objects backed by shmem buffers");
MODULE_LICENSE("GPL");
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