drm/i915/gem: Fix the mman selftest

Using the I915_MMAP_TYPE_FIXED mmap type requires the TTM backend, so
for that mmap type, use __i915_gem_object_create_user() instead of
i915_gem_object_create_internal(), as we really want to tests objects
mmap-able by user-space.

This also means that the out-of-space error happens at object creation
and returns -ENXIO rather than -ENOSPC, so fix the code up to expect
that on out-of-offset-space errors.

Finally only use I915_MMAP_TYPE_FIXED for LMEM and SMEM for now if
testing on LMEM-capable devices. For stolen LMEM, we still take the
same path as for integrated, as that haven't been moved over to TTM yet,
and user-space should not be able to create out of stolen LMEM anyway.

v2:
 - Check the presence of the obj->ops->mmap_offset callback rather than
   hardcoding the supported mmap regions in can_mmap() (Maarten Lankhorst)

Fixes: 7961c5b6 ("drm/i915: Add TTM offset argument to mmap.")
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210831122931.157536-1-thomas.hellstrom@linux.intel.com

drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c

@@ -581,6 +581,20 @@ static enum i915_mmap_type default_mapping(struct drm_i915_private *i915)
 	return I915_MMAP_TYPE_GTT;
 }
 
+static struct drm_i915_gem_object *
+create_sys_or_internal(struct drm_i915_private *i915,
+		       unsigned long size)
+{
+	if (HAS_LMEM(i915)) {
+		struct intel_memory_region *sys_region =
+			i915->mm.regions[INTEL_REGION_SMEM];
+
+		return __i915_gem_object_create_user(i915, size, &sys_region, 1);
+	}
+
+	return i915_gem_object_create_internal(i915, size);
+}
+
 static bool assert_mmap_offset(struct drm_i915_private *i915,
 			       unsigned long size,
 			       int expected)
@@ -589,7 +603,7 @@ static bool assert_mmap_offset(struct drm_i915_private *i915,
 	u64 offset;
 	int ret;
 
-	obj = i915_gem_object_create_internal(i915, size);
+	obj = create_sys_or_internal(i915, size);
 	if (IS_ERR(obj))
 		return expected && expected == PTR_ERR(obj);
 
@@ -633,6 +647,7 @@ static int igt_mmap_offset_exhaustion(void *arg)
 	struct drm_mm_node *hole, *next;
 	int loop, err = 0;
 	u64 offset;
+	int enospc = HAS_LMEM(i915) ? -ENXIO : -ENOSPC;
 
 	/* Disable background reaper */
 	disable_retire_worker(i915);
@@ -683,14 +698,14 @@ static int igt_mmap_offset_exhaustion(void *arg)
 	}
 
 	/* Too large */
-	if (!assert_mmap_offset(i915, 2 * PAGE_SIZE, -ENOSPC)) {
+	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);
+	obj = create_sys_or_internal(i915, PAGE_SIZE);
 	if (IS_ERR(obj)) {
 		err = PTR_ERR(obj);
 		pr_err("Unable to create object for reclaimed hole\n");
@@ -703,7 +718,7 @@ static int igt_mmap_offset_exhaustion(void *arg)
 		goto err_obj;
 	}
 
-	if (!assert_mmap_offset(i915, PAGE_SIZE, -ENOSPC)) {
+	if (!assert_mmap_offset(i915, PAGE_SIZE, enospc)) {
 		pr_err("Unexpectedly succeeded in inserting object into no holes!\n");
 		err = -EINVAL;
 		goto err_obj;
@@ -839,10 +854,9 @@ static int wc_check(struct drm_i915_gem_object *obj)
 
 static bool can_mmap(struct drm_i915_gem_object *obj, enum i915_mmap_type type)
 {
-	struct drm_i915_private *i915 = to_i915(obj->base.dev);
 	bool no_map;
 
-	if (HAS_LMEM(i915))
+	if (obj->ops->mmap_offset)
 		return type == I915_MMAP_TYPE_FIXED;
 	else if (type == I915_MMAP_TYPE_FIXED)
 		return false;