[Intel-gfx] [PATCH v3] drm/i915/gvt: return the actual aperture size under gvt environment

[Weinan Li]

I915_GEM_GET_APERTURE ioctl is used to probe aperture size from userspace.
In gvt environment, each vm only use the ballooned part of aperture, so we
should return the actual available aperture size exclude the reserved part
by balloon.

v2: add 'reserved' in struct i915_address_space to record the reserved size
in ggtt by balloon.

v3: remain aper_size as total, adjust aper_available_size exclude reserved
and pinned. UMD driver need to adjust the max allocation size according to
the available aperture size but not total size.

Signed-off-by: Weinan Li <weinan.z.li at intel.com>
---
 drivers/gpu/drm/i915/i915_gem.c     | 7 +++----
 drivers/gpu/drm/i915/i915_gem_gtt.h | 3 ++-
 drivers/gpu/drm/i915/i915_vgpu.c    | 5 ++++-
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 84ea249..e84576c 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -145,9 +145,8 @@ int i915_mutex_lock_interruptible(struct drm_device *dev)
 	struct i915_ggtt *ggtt = &dev_priv->ggtt;
 	struct drm_i915_gem_get_aperture *args = data;
 	struct i915_vma *vma;
-	size_t pinned;
+	size_t pinned = 0;
 
-	pinned = 0;
 	mutex_lock(&dev->struct_mutex);
 	list_for_each_entry(vma, &ggtt->base.active_list, vm_link)
 		if (i915_vma_is_pinned(vma))
@@ -158,8 +157,8 @@ int i915_mutex_lock_interruptible(struct drm_device *dev)
 	mutex_unlock(&dev->struct_mutex);
 
 	args->aper_size = ggtt->base.total;
-	args->aper_available_size = args->aper_size - pinned;
-
+	args->aper_available_size = args->aper_size
+			- ggtt->base.reserved - pinned;
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index fb15684..bdf832d 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -255,7 +255,8 @@ struct i915_address_space {
 	struct drm_i915_file_private *file;
 	struct list_head global_link;
 	u64 total;		/* size addr space maps (ex. 2GB for ggtt) */
-
+	/* size addr space reserved by GVT balloon, only used for ggtt */
+	u64 reserved;
 	bool closed;
 
 	struct i915_page_dma scratch_page;
diff --git a/drivers/gpu/drm/i915/i915_vgpu.c b/drivers/gpu/drm/i915/i915_vgpu.c
index 4ab8a97..58055a9 100644
--- a/drivers/gpu/drm/i915/i915_vgpu.c
+++ b/drivers/gpu/drm/i915/i915_vgpu.c
@@ -183,7 +183,7 @@ int intel_vgt_balloon(struct drm_i915_private *dev_priv)
 
 	unsigned long mappable_base, mappable_size, mappable_end;
 	unsigned long unmappable_base, unmappable_size, unmappable_end;
-	int ret;
+	int ret, i;
 
 	if (!intel_vgpu_active(dev_priv))
 		return 0;
@@ -242,6 +242,9 @@ int intel_vgt_balloon(struct drm_i915_private *dev_priv)
 			goto err;
 	}
 
+	for (i = 0; i < ARRAY_SIZE(bl_info.space); i++)
+		ggtt->base.reserved += bl_info.space[i].size;
+
 	DRM_INFO("VGT balloon successfully\n");
 	return 0;
 
-- 
1.9.1