drivers/gpu/drm/i915/selftests/i915_gem_object.c - arm/linux - Git at Google

 /*
  * Copyright © 2016 Intel Corporation
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice (including the next
  * paragraph) shall be included in all copies or substantial portions of the
  * Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  * IN THE SOFTWARE.
  *
  */

 #include "../i915_selftest.h"

 #include "mock_gem_device.h"
 #include "huge_gem_object.h"

 static int igt_gem_object(void *arg)
 {
 	struct drm_i915_private *i915 = arg;
 	struct drm_i915_gem_object *obj;
 	int err = -ENOMEM;

 	/* Basic test to ensure we can create an object */

 	obj = i915_gem_object_create(i915, PAGE_SIZE);
 	if (IS_ERR(obj)) {
 		err = PTR_ERR(obj);
 		pr_err("i915_gem_object_create failed, err=%d\n", err);
 		goto out;
 	}

 	err = 0;
 	i915_gem_object_put(obj);
 out:
 	return err;
 }

 static int igt_phys_object(void *arg)
 {
 	struct drm_i915_private *i915 = arg;
 	struct drm_i915_gem_object *obj;
 	int err;

 	/* Create an object and bind it to a contiguous set of physical pages,
 	 * i.e. exercise the i915_gem_object_phys API.
 	 */

 	obj = i915_gem_object_create(i915, PAGE_SIZE);
 	if (IS_ERR(obj)) {
 		err = PTR_ERR(obj);
 		pr_err("i915_gem_object_create failed, err=%d\n", err);
 		goto out;
 	}

 	mutex_lock(&i915->drm.struct_mutex);
 	err = i915_gem_object_attach_phys(obj, PAGE_SIZE);
 	mutex_unlock(&i915->drm.struct_mutex);
 	if (err) {
 		pr_err("i915_gem_object_attach_phys failed, err=%d\n", err);
 		goto out_obj;
 	}

 	if (obj->ops != &i915_gem_phys_ops) {
 		pr_err("i915_gem_object_attach_phys did not create a phys object\n");
 		err = -EINVAL;
 		goto out_obj;
 	}

 	if (!atomic_read(&obj->mm.pages_pin_count)) {
 		pr_err("i915_gem_object_attach_phys did not pin its phys pages\n");
 		err = -EINVAL;
 		goto out_obj;
 	}

 	/* Make the object dirty so that put_pages must do copy back the data */
 	mutex_lock(&i915->drm.struct_mutex);
 	err = i915_gem_object_set_to_gtt_domain(obj, true);
 	mutex_unlock(&i915->drm.struct_mutex);
 	if (err) {
 		pr_err("i915_gem_object_set_to_gtt_domain failed with err=%d\n",
 		       err);
 		goto out_obj;
 	}

 out_obj:
 	i915_gem_object_put(obj);
 out:
 	return err;
 }

 static int igt_gem_huge(void *arg)
 {
 	const unsigned int nreal = 509; /* just to be awkward */
 	struct drm_i915_private *i915 = arg;
 	struct drm_i915_gem_object *obj;
 	unsigned int n;
 	int err;

 	/* Basic sanitycheck of our huge fake object allocation */

 	obj = huge_gem_object(i915,
 			      nreal * PAGE_SIZE,
 			      i915->ggtt.base.total + PAGE_SIZE);
 	if (IS_ERR(obj))
 		return PTR_ERR(obj);

 	err = i915_gem_object_pin_pages(obj);
 	if (err) {
 		pr_err("Failed to allocate %u pages (%lu total), err=%d\n",
 		       nreal, obj->base.size / PAGE_SIZE, err);
 		goto out;
 	}

 	for (n = 0; n < obj->base.size / PAGE_SIZE; n++) {
 		if (i915_gem_object_get_page(obj, n) !=
 		    i915_gem_object_get_page(obj, n % nreal)) {
 			pr_err("Page lookup mismatch at index %u [%u]\n",
 			       n, n % nreal);
 			err = -EINVAL;
 			goto out_unpin;
 		}
 	}

 out_unpin:
 	i915_gem_object_unpin_pages(obj);
 out:
 	i915_gem_object_put(obj);
 	return err;
 }

 struct tile {
 	unsigned int width;
 	unsigned int height;
 	unsigned int stride;
 	unsigned int size;
 	unsigned int tiling;
 	unsigned int swizzle;
 };

 static u64 swizzle_bit(unsigned int bit, u64 offset)
 {
 	return (offset & BIT_ULL(bit)) >> (bit - 6);
 }

 static u64 tiled_offset(const struct tile *tile, u64 v)
 {
 	u64 x, y;

 	if (tile->tiling == I915_TILING_NONE)
 		return v;

 	y = div64_u64_rem(v, tile->stride, &x);
 	v = div64_u64_rem(y, tile->height, &y) * tile->stride * tile->height;

 	if (tile->tiling == I915_TILING_X) {
 		v += y * tile->width;
 		v += div64_u64_rem(x, tile->width, &x) << tile->size;
 		v += x;
 	} else {
 		const unsigned int ytile_span = 16;
 		const unsigned int ytile_height = 32 * ytile_span;

 		v += y * ytile_span;
 		v += div64_u64_rem(x, ytile_span, &x) * ytile_height;
 		v += x;
 	}

 	switch (tile->swizzle) {
 	case I915_BIT_6_SWIZZLE_9:
 		v ^= swizzle_bit(9, v);
 		break;
 	case I915_BIT_6_SWIZZLE_9_10:
 		v ^= swizzle_bit(9, v) ^ swizzle_bit(10, v);
 		break;
 	case I915_BIT_6_SWIZZLE_9_11:
 		v ^= swizzle_bit(9, v) ^ swizzle_bit(11, v);
 		break;
 	case I915_BIT_6_SWIZZLE_9_10_11:
 		v ^= swizzle_bit(9, v) ^ swizzle_bit(10, v) ^ swizzle_bit(11, v);
 		break;
 	}

 	return v;
 }

 static int check_partial_mapping(struct drm_i915_gem_object *obj,
 				 const struct tile *tile,
 				 unsigned long end_time)
 {
 	const unsigned int nreal = obj->scratch / PAGE_SIZE;
 	const unsigned long npages = obj->base.size / PAGE_SIZE;
 	struct i915_vma *vma;
 	unsigned long page;
 	int err;

 	if (igt_timeout(end_time,
 			"%s: timed out before tiling=%d stride=%d\n",
 			__func__, tile->tiling, tile->stride))
 		return -EINTR;

 	err = i915_gem_object_set_tiling(obj, tile->tiling, tile->stride);
 	if (err)
 		return err;

 	GEM_BUG_ON(i915_gem_object_get_tiling(obj) != tile->tiling);
 	GEM_BUG_ON(i915_gem_object_get_stride(obj) != tile->stride);

 	for_each_prime_number_from(page, 1, npages) {
 		struct i915_ggtt_view view =
 			compute_partial_view(obj, page, MIN_CHUNK_PAGES);
 		u32 __iomem *io;
 		struct page *p;
 		unsigned int n;
 		u64 offset;
 		u32 *cpu;

 		GEM_BUG_ON(view.partial.size > nreal);

 		err = i915_gem_object_set_to_gtt_domain(obj, true);
 		if (err)
 			return err;

 		vma = i915_gem_object_ggtt_pin(obj, &view, 0, 0, PIN_MAPPABLE);
 		if (IS_ERR(vma)) {
 			pr_err("Failed to pin partial view: offset=%lu\n",
 			       page);
 			return PTR_ERR(vma);
 		}

 		n = page - view.partial.offset;
 		GEM_BUG_ON(n >= view.partial.size);

 		io = i915_vma_pin_iomap(vma);
 		i915_vma_unpin(vma);
 		if (IS_ERR(io)) {
 			pr_err("Failed to iomap partial view: offset=%lu\n",
 			       page);
 			return PTR_ERR(io);
 		}

 		iowrite32(page, io + n * PAGE_SIZE/sizeof(*io));
 		i915_vma_unpin_iomap(vma);

 		offset = tiled_offset(tile, page << PAGE_SHIFT);
 		if (offset >= obj->base.size)
 			continue;

 		flush_write_domain(obj, ~I915_GEM_DOMAIN_CPU);

 		p = i915_gem_object_get_page(obj, offset >> PAGE_SHIFT);
 		cpu = kmap(p) + offset_in_page(offset);
 		drm_clflush_virt_range(cpu, sizeof(*cpu));
 		if (*cpu != (u32)page) {
 			pr_err("Partial view for %lu [%u] (offset=%llu, size=%u [%llu, row size %u], fence=%d, tiling=%d, stride=%d) misalignment, expected write to page (%llu + %u [0x%llx]) of 0x%x, found 0x%x\n",
 			       page, n,
 			       view.partial.offset,
 			       view.partial.size,
 			       vma->size >> PAGE_SHIFT,
 			       tile_row_pages(obj),
 			       vma->fence ? vma->fence->id : -1, tile->tiling, tile->stride,
 			       offset >> PAGE_SHIFT,
 			       (unsigned int)offset_in_page(offset),
 			       offset,
 			       (u32)page, *cpu);
 			err = -EINVAL;
 		}
 		*cpu = 0;
 		drm_clflush_virt_range(cpu, sizeof(*cpu));
 		kunmap(p);
 		if (err)
 			return err;
 	}

 	return 0;
 }

 static int igt_partial_tiling(void *arg)
 {
 	const unsigned int nreal = 1 << 12; /* largest tile row x2 */
 	struct drm_i915_private *i915 = arg;
 	struct drm_i915_gem_object *obj;
 	int tiling;
 	int err;

 	/* We want to check the page mapping and fencing of a large object
 	 * mmapped through the GTT. The object we create is larger than can
 	 * possibly be mmaped as a whole, and so we must use partial GGTT vma.
 	 * We then check that a write through each partial GGTT vma ends up
 	 * in the right set of pages within the object, and with the expected
 	 * tiling, which we verify by manual swizzling.
 	 */

 	obj = huge_gem_object(i915,
 			      nreal << PAGE_SHIFT,
 			      (1 + next_prime_number(i915->ggtt.base.total >> PAGE_SHIFT)) << PAGE_SHIFT);
 	if (IS_ERR(obj))
 		return PTR_ERR(obj);

 	err = i915_gem_object_pin_pages(obj);
 	if (err) {
 		pr_err("Failed to allocate %u pages (%lu total), err=%d\n",
 		       nreal, obj->base.size / PAGE_SIZE, err);
 		goto out;
 	}

 	mutex_lock(&i915->drm.struct_mutex);

 	if (1) {
 		IGT_TIMEOUT(end);
 		struct tile tile;

 		tile.height = 1;
 		tile.width = 1;
 		tile.size = 0;
 		tile.stride = 0;
 		tile.swizzle = I915_BIT_6_SWIZZLE_NONE;
 		tile.tiling = I915_TILING_NONE;

 		err = check_partial_mapping(obj, &tile, end);
 		if (err && err != -EINTR)
 			goto out_unlock;
 	}

 	for (tiling = I915_TILING_X; tiling <= I915_TILING_Y; tiling++) {
 		IGT_TIMEOUT(end);
 		unsigned int max_pitch;
 		unsigned int pitch;
 		struct tile tile;

 		tile.tiling = tiling;
 		switch (tiling) {
 		case I915_TILING_X:
 			tile.swizzle = i915->mm.bit_6_swizzle_x;
 			break;
 		case I915_TILING_Y:
 			tile.swizzle = i915->mm.bit_6_swizzle_y;
 			break;
 		}

 		if (tile.swizzle == I915_BIT_6_SWIZZLE_UNKNOWN ||
 		    tile.swizzle == I915_BIT_6_SWIZZLE_9_10_17)
 			continue;

 		if (INTEL_GEN(i915) <= 2) {
 			tile.height = 16;
 			tile.width = 128;
 			tile.size = 11;
 		} else if (tile.tiling == I915_TILING_Y &&
 			   HAS_128_BYTE_Y_TILING(i915)) {
 			tile.height = 32;
 			tile.width = 128;
 			tile.size = 12;
 		} else {
 			tile.height = 8;
 			tile.width = 512;
 			tile.size = 12;
 		}

 		if (INTEL_GEN(i915) < 4)
 			max_pitch = 8192 / tile.width;
 		else if (INTEL_GEN(i915) < 7)
 			max_pitch = 128 * I965_FENCE_MAX_PITCH_VAL / tile.width;
 		else
 			max_pitch = 128 * GEN7_FENCE_MAX_PITCH_VAL / tile.width;

 		for (pitch = max_pitch; pitch; pitch >>= 1) {
 			tile.stride = tile.width * pitch;
 			err = check_partial_mapping(obj, &tile, end);
 			if (err == -EINTR)
 				goto next_tiling;
 			if (err)
 				goto out_unlock;

 			if (pitch > 2 && INTEL_GEN(i915) >= 4) {
 				tile.stride = tile.width * (pitch - 1);
 				err = check_partial_mapping(obj, &tile, end);
 				if (err == -EINTR)
 					goto next_tiling;
 				if (err)
 					goto out_unlock;
 			}

 			if (pitch < max_pitch && INTEL_GEN(i915) >= 4) {
 				tile.stride = tile.width * (pitch + 1);
 				err = check_partial_mapping(obj, &tile, end);
 				if (err == -EINTR)
 					goto next_tiling;
 				if (err)
 					goto out_unlock;
 			}
 		}

 		if (INTEL_GEN(i915) >= 4) {
 			for_each_prime_number(pitch, max_pitch) {
 				tile.stride = tile.width * pitch;
 				err = check_partial_mapping(obj, &tile, end);
 				if (err == -EINTR)
 					goto next_tiling;
 				if (err)
 					goto out_unlock;
 			}
 		}

 next_tiling: ;
 	}

 out_unlock:
 	mutex_unlock(&i915->drm.struct_mutex);
 	i915_gem_object_unpin_pages(obj);
 out:
 	i915_gem_object_put(obj);
 	return err;
 }

 static int make_obj_busy(struct drm_i915_gem_object *obj)
 {
 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
 	struct drm_i915_gem_request *rq;
 	struct i915_vma *vma;
 	int err;

 	vma = i915_vma_instance(obj, &i915->ggtt.base, NULL);
 	if (IS_ERR(vma))
 		return PTR_ERR(vma);

 	err = i915_vma_pin(vma, 0, 0, PIN_USER);
 	if (err)
 		return err;

 	rq = i915_gem_request_alloc(i915->engine[RCS], i915->kernel_context);
 	if (IS_ERR(rq)) {
 		i915_vma_unpin(vma);
 		return PTR_ERR(rq);
 	}

 	i915_vma_move_to_active(vma, rq, 0);
 	i915_add_request(rq);

 	i915_gem_object_set_active_reference(obj);
 	i915_vma_unpin(vma);
 	return 0;
 }

 static bool assert_mmap_offset(struct drm_i915_private *i915,
 			       unsigned long size,
 			       int expected)
 {
 	struct drm_i915_gem_object *obj;
 	int err;

 	obj = i915_gem_object_create_internal(i915, size);
 	if (IS_ERR(obj))
 		return PTR_ERR(obj);

 	err = i915_gem_object_create_mmap_offset(obj);
 	i915_gem_object_put(obj);

 	return err == expected;
 }

 static int igt_mmap_offset_exhaustion(void *arg)
 {
 	struct drm_i915_private *i915 = arg;
 	struct drm_mm *mm = &i915->drm.vma_offset_manager->vm_addr_space_mm;
 	struct drm_i915_gem_object *obj;
 	struct drm_mm_node resv, *hole;
 	u64 hole_start, hole_end;
 	int loop, err;

 	/* Trim the device mmap space to only a page */
 	memset(&resv, 0, sizeof(resv));
 	drm_mm_for_each_hole(hole, mm, hole_start, hole_end) {
 		resv.start = hole_start;
 		resv.size = hole_end - hole_start - 1; /* PAGE_SIZE units */
 		err = drm_mm_reserve_node(mm, &resv);
 		if (err) {
 			pr_err("Failed to trim VMA manager, err=%d\n", err);
 			return err;
 		}
 		break;
 	}

 	/* Just fits! */
 	if (!assert_mmap_offset(i915, PAGE_SIZE, 0)) {
 		pr_err("Unable to insert object into single page hole\n");
 		err = -EINVAL;
 		goto out;
 	}

 	/* Too large */
 	if (!assert_mmap_offset(i915, 2*PAGE_SIZE, -ENOSPC)) {
 		pr_err("Unexpectedly succeeded in inserting too large object into single page hole\n");
 		err = -EINVAL;
 		goto out;
 	}

 	/* Fill the hole, further allocation attempts should then fail */
 	obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
 	if (IS_ERR(obj)) {
 		err = PTR_ERR(obj);
 		goto out;
 	}

 	err = i915_gem_object_create_mmap_offset(obj);
 	if (err) {
 		pr_err("Unable to insert object into reclaimed hole\n");
 		goto err_obj;
 	}

 	if (!assert_mmap_offset(i915, PAGE_SIZE, -ENOSPC)) {
 		pr_err("Unexpectedly succeeded in inserting object into no holes!\n");
 		err = -EINVAL;
 		goto err_obj;
 	}

 	i915_gem_object_put(obj);

 	/* Now fill with busy dead objects that we expect to reap */
 	for (loop = 0; loop < 3; loop++) {
 		obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
 		if (IS_ERR(obj)) {
 			err = PTR_ERR(obj);
 			goto out;
 		}

 		mutex_lock(&i915->drm.struct_mutex);
 		intel_runtime_pm_get(i915);
 		err = make_obj_busy(obj);
 		intel_runtime_pm_put(i915);
 		mutex_unlock(&i915->drm.struct_mutex);
 		if (err) {
 			pr_err("[loop %d] Failed to busy the object\n", loop);
 			goto err_obj;
 		}

 		GEM_BUG_ON(!i915_gem_object_is_active(obj));
 		err = i915_gem_object_create_mmap_offset(obj);
 		if (err) {
 			pr_err("[loop %d] i915_gem_object_create_mmap_offset failed with err=%d\n",
 			       loop, err);
 			goto out;
 		}
 	}

 out:
 	drm_mm_remove_node(&resv);
 	return err;
 err_obj:
 	i915_gem_object_put(obj);
 	goto out;
 }

 int i915_gem_object_mock_selftests(void)
 {
 	static const struct i915_subtest tests[] = {
 		SUBTEST(igt_gem_object),
 		SUBTEST(igt_phys_object),
 	};
 	struct drm_i915_private *i915;
 	int err;

 	i915 = mock_gem_device();
 	if (!i915)
 		return -ENOMEM;

 	err = i915_subtests(tests, i915);

 	drm_dev_unref(&i915->drm);
 	return err;
 }

 int i915_gem_object_live_selftests(struct drm_i915_private *i915)
 {
 	static const struct i915_subtest tests[] = {
 		SUBTEST(igt_gem_huge),
 		SUBTEST(igt_partial_tiling),
 		SUBTEST(igt_mmap_offset_exhaustion),
 	};

 	return i915_subtests(tests, i915);
 }
	/*
	* Copyright © 2016 Intel Corporation
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the "Software"),
	* to deal in the Software without restriction, including without limitation
	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	* and/or sell copies of the Software, and to permit persons to whom the
	* Software is furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice (including the next
	* paragraph) shall be included in all copies or substantial portions of the
	* Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
	* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
	* IN THE SOFTWARE.
	*
	*/

	#include "../i915_selftest.h"

	#include "mock_gem_device.h"
	#include "huge_gem_object.h"

	static int igt_gem_object(void *arg)
	{
	struct drm_i915_private *i915 = arg;
	struct drm_i915_gem_object *obj;
	int err = -ENOMEM;

	/* Basic test to ensure we can create an object */

	obj = i915_gem_object_create(i915, PAGE_SIZE);
	if (IS_ERR(obj)) {
	err = PTR_ERR(obj);
	pr_err("i915_gem_object_create failed, err=%d\n", err);
	goto out;
	}

	err = 0;
	i915_gem_object_put(obj);
	out:
	return err;
	}

	static int igt_phys_object(void *arg)
	{
	struct drm_i915_private *i915 = arg;
	struct drm_i915_gem_object *obj;
	int err;

	/* Create an object and bind it to a contiguous set of physical pages,
	* i.e. exercise the i915_gem_object_phys API.
	*/

	obj = i915_gem_object_create(i915, PAGE_SIZE);
	if (IS_ERR(obj)) {
	err = PTR_ERR(obj);
	pr_err("i915_gem_object_create failed, err=%d\n", err);
	goto out;
	}

	mutex_lock(&i915->drm.struct_mutex);
	err = i915_gem_object_attach_phys(obj, PAGE_SIZE);
	mutex_unlock(&i915->drm.struct_mutex);
	if (err) {
	pr_err("i915_gem_object_attach_phys failed, err=%d\n", err);
	goto out_obj;
	}

	if (obj->ops != &i915_gem_phys_ops) {
	pr_err("i915_gem_object_attach_phys did not create a phys object\n");
	err = -EINVAL;
	goto out_obj;
	}

	if (!atomic_read(&obj->mm.pages_pin_count)) {
	pr_err("i915_gem_object_attach_phys did not pin its phys pages\n");
	err = -EINVAL;
	goto out_obj;
	}

	/* Make the object dirty so that put_pages must do copy back the data */
	mutex_lock(&i915->drm.struct_mutex);
	err = i915_gem_object_set_to_gtt_domain(obj, true);
	mutex_unlock(&i915->drm.struct_mutex);
	if (err) {
	pr_err("i915_gem_object_set_to_gtt_domain failed with err=%d\n",
	err);
	goto out_obj;
	}

	out_obj:
	i915_gem_object_put(obj);
	out:
	return err;
	}

	static int igt_gem_huge(void *arg)
	{
	const unsigned int nreal = 509; /* just to be awkward */
	struct drm_i915_private *i915 = arg;
	struct drm_i915_gem_object *obj;
	unsigned int n;
	int err;

	/* Basic sanitycheck of our huge fake object allocation */

	obj = huge_gem_object(i915,
	nreal * PAGE_SIZE,
	i915->ggtt.base.total + PAGE_SIZE);
	if (IS_ERR(obj))
	return PTR_ERR(obj);

	err = i915_gem_object_pin_pages(obj);
	if (err) {
	pr_err("Failed to allocate %u pages (%lu total), err=%d\n",
	nreal, obj->base.size / PAGE_SIZE, err);
	goto out;
	}

	for (n = 0; n < obj->base.size / PAGE_SIZE; n++) {
	if (i915_gem_object_get_page(obj, n) !=
	i915_gem_object_get_page(obj, n % nreal)) {
	pr_err("Page lookup mismatch at index %u [%u]\n",
	n, n % nreal);
	err = -EINVAL;
	goto out_unpin;
	}
	}

	out_unpin:
	i915_gem_object_unpin_pages(obj);
	out:
	i915_gem_object_put(obj);
	return err;
	}

	struct tile {
	unsigned int width;
	unsigned int height;
	unsigned int stride;
	unsigned int size;
	unsigned int tiling;
	unsigned int swizzle;
	};

	static u64 swizzle_bit(unsigned int bit, u64 offset)
	{
	return (offset & BIT_ULL(bit)) >> (bit - 6);
	}

	static u64 tiled_offset(const struct tile *tile, u64 v)
	{
	u64 x, y;

	if (tile->tiling == I915_TILING_NONE)
	return v;

	y = div64_u64_rem(v, tile->stride, &x);
	v = div64_u64_rem(y, tile->height, &y) * tile->stride * tile->height;

	if (tile->tiling == I915_TILING_X) {
	v += y * tile->width;
	v += div64_u64_rem(x, tile->width, &x) << tile->size;
	v += x;
	} else {
	const unsigned int ytile_span = 16;
	const unsigned int ytile_height = 32 * ytile_span;

	v += y * ytile_span;
	v += div64_u64_rem(x, ytile_span, &x) * ytile_height;
	v += x;
	}

	switch (tile->swizzle) {
	case I915_BIT_6_SWIZZLE_9:
	v ^= swizzle_bit(9, v);
	break;
	case I915_BIT_6_SWIZZLE_9_10:
	v ^= swizzle_bit(9, v) ^ swizzle_bit(10, v);
	break;
	case I915_BIT_6_SWIZZLE_9_11:
	v ^= swizzle_bit(9, v) ^ swizzle_bit(11, v);
	break;
	case I915_BIT_6_SWIZZLE_9_10_11:
	v ^= swizzle_bit(9, v) ^ swizzle_bit(10, v) ^ swizzle_bit(11, v);
	break;
	}

	return v;
	}

	static int check_partial_mapping(struct drm_i915_gem_object *obj,
	const struct tile *tile,
	unsigned long end_time)
	{
	const unsigned int nreal = obj->scratch / PAGE_SIZE;
	const unsigned long npages = obj->base.size / PAGE_SIZE;
	struct i915_vma *vma;
	unsigned long page;
	int err;

	if (igt_timeout(end_time,
	"%s: timed out before tiling=%d stride=%d\n",
	__func__, tile->tiling, tile->stride))
	return -EINTR;

	err = i915_gem_object_set_tiling(obj, tile->tiling, tile->stride);
	if (err)
	return err;

	GEM_BUG_ON(i915_gem_object_get_tiling(obj) != tile->tiling);
	GEM_BUG_ON(i915_gem_object_get_stride(obj) != tile->stride);

	for_each_prime_number_from(page, 1, npages) {
	struct i915_ggtt_view view =
	compute_partial_view(obj, page, MIN_CHUNK_PAGES);
	u32 __iomem *io;
	struct page *p;
	unsigned int n;
	u64 offset;
	u32 *cpu;

	GEM_BUG_ON(view.partial.size > nreal);

	err = i915_gem_object_set_to_gtt_domain(obj, true);
	if (err)
	return err;

	vma = i915_gem_object_ggtt_pin(obj, &view, 0, 0, PIN_MAPPABLE);
	if (IS_ERR(vma)) {
	pr_err("Failed to pin partial view: offset=%lu\n",
	page);
	return PTR_ERR(vma);
	}

	n = page - view.partial.offset;
	GEM_BUG_ON(n >= view.partial.size);

	io = i915_vma_pin_iomap(vma);
	i915_vma_unpin(vma);
	if (IS_ERR(io)) {
	pr_err("Failed to iomap partial view: offset=%lu\n",
	page);
	return PTR_ERR(io);
	}

	iowrite32(page, io + n * PAGE_SIZE/sizeof(*io));
	i915_vma_unpin_iomap(vma);

	offset = tiled_offset(tile, page << PAGE_SHIFT);
	if (offset >= obj->base.size)
	continue;

	flush_write_domain(obj, ~I915_GEM_DOMAIN_CPU);

	p = i915_gem_object_get_page(obj, offset >> PAGE_SHIFT);
	cpu = kmap(p) + offset_in_page(offset);
	drm_clflush_virt_range(cpu, sizeof(*cpu));
	if (*cpu != (u32)page) {
	pr_err("Partial view for %lu [%u] (offset=%llu, size=%u [%llu, row size %u], fence=%d, tiling=%d, stride=%d) misalignment, expected write to page (%llu + %u [0x%llx]) of 0x%x, found 0x%x\n",
	page, n,
	view.partial.offset,
	view.partial.size,
	vma->size >> PAGE_SHIFT,
	tile_row_pages(obj),
	vma->fence ? vma->fence->id : -1, tile->tiling, tile->stride,
	offset >> PAGE_SHIFT,
	(unsigned int)offset_in_page(offset),
	offset,
	(u32)page, *cpu);
	err = -EINVAL;
	}
	*cpu = 0;
	drm_clflush_virt_range(cpu, sizeof(*cpu));
	kunmap(p);
	if (err)
	return err;
	}

	return 0;
	}

	static int igt_partial_tiling(void *arg)
	{
	const unsigned int nreal = 1 << 12; /* largest tile row x2 */
	struct drm_i915_private *i915 = arg;
	struct drm_i915_gem_object *obj;
	int tiling;
	int err;

	/* We want to check the page mapping and fencing of a large object
	* mmapped through the GTT. The object we create is larger than can
	* possibly be mmaped as a whole, and so we must use partial GGTT vma.
	* We then check that a write through each partial GGTT vma ends up
	* in the right set of pages within the object, and with the expected
	* tiling, which we verify by manual swizzling.
	*/

	obj = huge_gem_object(i915,
	nreal << PAGE_SHIFT,
	(1 + next_prime_number(i915->ggtt.base.total >> PAGE_SHIFT)) << PAGE_SHIFT);
	if (IS_ERR(obj))
	return PTR_ERR(obj);

	err = i915_gem_object_pin_pages(obj);
	if (err) {
	pr_err("Failed to allocate %u pages (%lu total), err=%d\n",
	nreal, obj->base.size / PAGE_SIZE, err);
	goto out;
	}

	mutex_lock(&i915->drm.struct_mutex);

	if (1) {
	IGT_TIMEOUT(end);
	struct tile tile;

	tile.height = 1;
	tile.width = 1;
	tile.size = 0;
	tile.stride = 0;
	tile.swizzle = I915_BIT_6_SWIZZLE_NONE;
	tile.tiling = I915_TILING_NONE;

	err = check_partial_mapping(obj, &tile, end);
	if (err && err != -EINTR)
	goto out_unlock;
	}

	for (tiling = I915_TILING_X; tiling <= I915_TILING_Y; tiling++) {
	IGT_TIMEOUT(end);
	unsigned int max_pitch;
	unsigned int pitch;
	struct tile tile;

	tile.tiling = tiling;
	switch (tiling) {
	case I915_TILING_X:
	tile.swizzle = i915->mm.bit_6_swizzle_x;
	break;
	case I915_TILING_Y:
	tile.swizzle = i915->mm.bit_6_swizzle_y;
	break;
	}

	if (tile.swizzle == I915_BIT_6_SWIZZLE_UNKNOWN \|\|
	tile.swizzle == I915_BIT_6_SWIZZLE_9_10_17)
	continue;

	if (INTEL_GEN(i915) <= 2) {
	tile.height = 16;
	tile.width = 128;
	tile.size = 11;
	} else if (tile.tiling == I915_TILING_Y &&
	HAS_128_BYTE_Y_TILING(i915)) {
	tile.height = 32;
	tile.width = 128;
	tile.size = 12;
	} else {
	tile.height = 8;
	tile.width = 512;
	tile.size = 12;
	}

	if (INTEL_GEN(i915) < 4)
	max_pitch = 8192 / tile.width;
	else if (INTEL_GEN(i915) < 7)
	max_pitch = 128 * I965_FENCE_MAX_PITCH_VAL / tile.width;
	else
	max_pitch = 128 * GEN7_FENCE_MAX_PITCH_VAL / tile.width;

	for (pitch = max_pitch; pitch; pitch >>= 1) {
	tile.stride = tile.width * pitch;
	err = check_partial_mapping(obj, &tile, end);
	if (err == -EINTR)
	goto next_tiling;
	if (err)
	goto out_unlock;

	if (pitch > 2 && INTEL_GEN(i915) >= 4) {
	tile.stride = tile.width * (pitch - 1);
	err = check_partial_mapping(obj, &tile, end);
	if (err == -EINTR)
	goto next_tiling;
	if (err)
	goto out_unlock;
	}

	if (pitch < max_pitch && INTEL_GEN(i915) >= 4) {
	tile.stride = tile.width * (pitch + 1);
	err = check_partial_mapping(obj, &tile, end);
	if (err == -EINTR)
	goto next_tiling;
	if (err)
	goto out_unlock;
	}
	}

	if (INTEL_GEN(i915) >= 4) {
	for_each_prime_number(pitch, max_pitch) {
	tile.stride = tile.width * pitch;
	err = check_partial_mapping(obj, &tile, end);
	if (err == -EINTR)
	goto next_tiling;
	if (err)
	goto out_unlock;
	}
	}

	next_tiling: ;
	}

	out_unlock:
	mutex_unlock(&i915->drm.struct_mutex);
	i915_gem_object_unpin_pages(obj);
	out:
	i915_gem_object_put(obj);
	return err;
	}

	static int make_obj_busy(struct drm_i915_gem_object *obj)
	{
	struct drm_i915_private *i915 = to_i915(obj->base.dev);
	struct drm_i915_gem_request *rq;
	struct i915_vma *vma;
	int err;

	vma = i915_vma_instance(obj, &i915->ggtt.base, NULL);
	if (IS_ERR(vma))
	return PTR_ERR(vma);

	err = i915_vma_pin(vma, 0, 0, PIN_USER);
	if (err)
	return err;

	rq = i915_gem_request_alloc(i915->engine[RCS], i915->kernel_context);
	if (IS_ERR(rq)) {
	i915_vma_unpin(vma);
	return PTR_ERR(rq);
	}

	i915_vma_move_to_active(vma, rq, 0);
	i915_add_request(rq);

	i915_gem_object_set_active_reference(obj);
	i915_vma_unpin(vma);
	return 0;
	}

	static bool assert_mmap_offset(struct drm_i915_private *i915,
	unsigned long size,
	int expected)
	{
	struct drm_i915_gem_object *obj;
	int err;

	obj = i915_gem_object_create_internal(i915, size);
	if (IS_ERR(obj))
	return PTR_ERR(obj);

	err = i915_gem_object_create_mmap_offset(obj);
	i915_gem_object_put(obj);

	return err == expected;
	}

	static int igt_mmap_offset_exhaustion(void *arg)
	{
	struct drm_i915_private *i915 = arg;
	struct drm_mm *mm = &i915->drm.vma_offset_manager->vm_addr_space_mm;
	struct drm_i915_gem_object *obj;
	struct drm_mm_node resv, *hole;
	u64 hole_start, hole_end;
	int loop, err;

	/* Trim the device mmap space to only a page */
	memset(&resv, 0, sizeof(resv));
	drm_mm_for_each_hole(hole, mm, hole_start, hole_end) {
	resv.start = hole_start;
	resv.size = hole_end - hole_start - 1; /* PAGE_SIZE units */
	err = drm_mm_reserve_node(mm, &resv);
	if (err) {
	pr_err("Failed to trim VMA manager, err=%d\n", err);
	return err;
	}
	break;
	}

	/* Just fits! */
	if (!assert_mmap_offset(i915, PAGE_SIZE, 0)) {
	pr_err("Unable to insert object into single page hole\n");
	err = -EINVAL;
	goto out;
	}

	/* Too large */
	if (!assert_mmap_offset(i915, 2*PAGE_SIZE, -ENOSPC)) {
	pr_err("Unexpectedly succeeded in inserting too large object into single page hole\n");
	err = -EINVAL;
	goto out;
	}

	/* Fill the hole, further allocation attempts should then fail */
	obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
	if (IS_ERR(obj)) {
	err = PTR_ERR(obj);
	goto out;
	}

	err = i915_gem_object_create_mmap_offset(obj);
	if (err) {
	pr_err("Unable to insert object into reclaimed hole\n");
	goto err_obj;
	}

	if (!assert_mmap_offset(i915, PAGE_SIZE, -ENOSPC)) {
	pr_err("Unexpectedly succeeded in inserting object into no holes!\n");
	err = -EINVAL;
	goto err_obj;
	}

	i915_gem_object_put(obj);

	/* Now fill with busy dead objects that we expect to reap */
	for (loop = 0; loop < 3; loop++) {
	obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
	if (IS_ERR(obj)) {
	err = PTR_ERR(obj);
	goto out;
	}

	mutex_lock(&i915->drm.struct_mutex);
	intel_runtime_pm_get(i915);
	err = make_obj_busy(obj);
	intel_runtime_pm_put(i915);
	mutex_unlock(&i915->drm.struct_mutex);
	if (err) {
	pr_err("[loop %d] Failed to busy the object\n", loop);
	goto err_obj;
	}

	GEM_BUG_ON(!i915_gem_object_is_active(obj));
	err = i915_gem_object_create_mmap_offset(obj);
	if (err) {
	pr_err("[loop %d] i915_gem_object_create_mmap_offset failed with err=%d\n",
	loop, err);
	goto out;
	}
	}

	out:
	drm_mm_remove_node(&resv);
	return err;
	err_obj:
	i915_gem_object_put(obj);
	goto out;
	}

	int i915_gem_object_mock_selftests(void)
	{
	static const struct i915_subtest tests[] = {
	SUBTEST(igt_gem_object),
	SUBTEST(igt_phys_object),
	};
	struct drm_i915_private *i915;
	int err;

	i915 = mock_gem_device();
	if (!i915)
	return -ENOMEM;

	err = i915_subtests(tests, i915);

	drm_dev_unref(&i915->drm);
	return err;
	}

	int i915_gem_object_live_selftests(struct drm_i915_private *i915)
	{
	static const struct i915_subtest tests[] = {
	SUBTEST(igt_gem_huge),
	SUBTEST(igt_partial_tiling),
	SUBTEST(igt_mmap_offset_exhaustion),
	};

	return i915_subtests(tests, i915);
	}