drm/i915: introduce intel_memory_region

Support memory regions, as defined by a given (start, end), and allow
creating GEM objects which are backed by said region. The immediate goal
here is to have something to represent our device memory, but later on
we also want to represent every memory domain with a region, so stolen,
shmem, and of course device. At some point we are probably going to want
use a common struct here, such that we are better aligned with say TTM.

Signed-off-by: Matthew Auld <[email protected]>
Signed-off-by: Abdiel Janulgue <[email protected]>
Signed-off-by: Niranjana Vishwanathapura <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Reviewed-by: Chris Wilson <[email protected]>
Signed-off-by: Chris Wilson <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

1 files changed, 115 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/selftests/intel_memory_region.c b/drivers/gpu/drm/i915/selftests/intel_memory_region.c
new file mode 100644
index 000000000000..89eaa419eaf2
--- /dev/null
+++ b/drivers/gpu/drm/i915/selftests/intel_memory_region.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2019 Intel Corporation
+ */
+
+#include <linux/prime_numbers.h>
+
+#include "../i915_selftest.h"
+
+#include "mock_drm.h"
+#include "mock_gem_device.h"
+#include "mock_region.h"
+
+#include "gem/i915_gem_region.h"
+#include "gem/selftests/mock_context.h"
+
+static void close_objects(struct intel_memory_region *mem,
+			  struct list_head *objects)
+{
+	struct drm_i915_private *i915 = mem->i915;
+	struct drm_i915_gem_object *obj, *on;
+
+	list_for_each_entry_safe(obj, on, objects, st_link) {
+		if (i915_gem_object_has_pinned_pages(obj))
+			i915_gem_object_unpin_pages(obj);
+		/* No polluting the memory region between tests */
+		__i915_gem_object_put_pages(obj, I915_MM_NORMAL);
+		list_del(&obj->st_link);
+		i915_gem_object_put(obj);
+	}
+
+	cond_resched();
+
+	i915_gem_drain_freed_objects(i915);
+}
+
+static int igt_mock_fill(void *arg)
+{
+	struct intel_memory_region *mem = arg;
+	resource_size_t total = resource_size(&mem->region);
+	resource_size_t page_size;
+	resource_size_t rem;
+	unsigned long max_pages;
+	unsigned long page_num;
+	LIST_HEAD(objects);
+	int err = 0;
+
+	page_size = mem->mm.chunk_size;
+	max_pages = div64_u64(total, page_size);
+	rem = total;
+
+	for_each_prime_number_from(page_num, 1, max_pages) {
+		resource_size_t size = page_num * page_size;
+		struct drm_i915_gem_object *obj;
+
+		obj = i915_gem_object_create_region(mem, size, 0);
+		if (IS_ERR(obj)) {
+			err = PTR_ERR(obj);
+			break;
+		}
+
+		err = i915_gem_object_pin_pages(obj);
+		if (err) {
+			i915_gem_object_put(obj);
+			break;
+		}
+
+		list_add(&obj->st_link, &objects);
+		rem -= size;
+	}
+
+	if (err == -ENOMEM)
+		err = 0;
+	if (err == -ENXIO) {
+		if (page_num * page_size <= rem) {
+			pr_err("%s failed, space still left in region\n",
+			       __func__);
+			err = -EINVAL;
+		} else {
+			err = 0;
+		}
+	}
+
+	close_objects(mem, &objects);
+
+	return err;
+}
+
+int intel_memory_region_mock_selftests(void)
+{
+	static const struct i915_subtest tests[] = {
+		SUBTEST(igt_mock_fill),
+	};
+	struct intel_memory_region *mem;
+	struct drm_i915_private *i915;
+	int err;
+
+	i915 = mock_gem_device();
+	if (!i915)
+		return -ENOMEM;
+
+	mem = mock_region_create(i915, 0, SZ_2G, I915_GTT_PAGE_SIZE_4K, 0);
+	if (IS_ERR(mem)) {
+		pr_err("failed to create memory region\n");
+		err = PTR_ERR(mem);
+		goto out_unref;
+	}
+
+	err = i915_subtests(tests, mem);
+
+	intel_memory_region_put(mem);
+out_unref:
+	drm_dev_put(&i915->drm);
+	return err;
+}