[Intel-gfx] [PATCH] 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.
Some applications like OpenCL use this information to know how much GM
resource can it use. In gvt environment, each vm only use the ballooned
part of aperture, so we should return the actual aperture size exclude
the reserved part by balloon.

I915_GEM_CONTEXT_GETPARAM ioctl query the I915_CONTEXT_PARAM_GTT_SIZE, we
also need to exclude the reserved part in GTT.

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_context.c |  4 +++-
 drivers/gpu/drm/i915/i915_vgpu.c        | 18 +++++++++++++++++-
 drivers/gpu/drm/i915/i915_vgpu.h        |  2 ++
 4 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 84ea249..b3fb424 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))
@@ -157,9 +156,9 @@ int i915_mutex_lock_interruptible(struct drm_device *dev)
 			pinned += vma->node.size;
 	mutex_unlock(&dev->struct_mutex);
 
-	args->aper_size = ggtt->base.total;
+	args->aper_size = ggtt->base.total -
+		 intel_vgt_reserved_size_by_balloon(dev_priv);
 	args->aper_available_size = args->aper_size - pinned;
-
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 8bd0c49..9f3280d 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -88,6 +88,7 @@
 #include <drm/drmP.h>
 #include <drm/i915_drm.h>
 #include "i915_drv.h"
+#include "i915_vgpu.h"
 #include "i915_trace.h"
 
 #define ALL_L3_SLICES(dev) (1 << NUM_L3_SLICES(dev)) - 1
@@ -1053,7 +1054,8 @@ int i915_gem_context_getparam_ioctl(struct drm_device *dev, void *data,
 		else if (to_i915(dev)->mm.aliasing_ppgtt)
 			args->value = to_i915(dev)->mm.aliasing_ppgtt->base.total;
 		else
-			args->value = to_i915(dev)->ggtt.base.total;
+			args->value = to_i915(dev)->ggtt.base.total -
+			  intel_vgt_reserved_size_by_balloon(dev->dev_private);
 		break;
 	case I915_CONTEXT_PARAM_NO_ERROR_CAPTURE:
 		args->value = i915_gem_context_no_error_capture(ctx);
diff --git a/drivers/gpu/drm/i915/i915_vgpu.c b/drivers/gpu/drm/i915/i915_vgpu.c
index 4ab8a97..ce722d8 100644
--- a/drivers/gpu/drm/i915/i915_vgpu.c
+++ b/drivers/gpu/drm/i915/i915_vgpu.c
@@ -88,6 +88,11 @@ struct _balloon_info_ {
 	 * graphic memory, 2/3 for unmappable graphic memory.
 	 */
 	struct drm_mm_node space[4];
+	/*
+	 * Total space size exclude ballooned named reserved_total, it's
+	 * invisible for vGPU.
+	 */
+	size_t reserved_total;
 };
 
 static struct _balloon_info_ bl_info;
@@ -116,6 +121,14 @@ void intel_vgt_deballoon(struct drm_i915_private *dev_priv)
 	memset(&bl_info, 0, sizeof(bl_info));
 }
 
+size_t intel_vgt_reserved_size_by_balloon(struct drm_i915_private *dev_priv)
+{
+	if (!intel_vgpu_active(dev_priv))
+		return 0;
+
+	return bl_info.reserved_total;
+}
+
 static int vgt_balloon_space(struct i915_ggtt *ggtt,
 			     struct drm_mm_node *node,
 			     unsigned long start, unsigned long end)
@@ -183,7 +196,7 @@ 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 +255,9 @@ int intel_vgt_balloon(struct drm_i915_private *dev_priv)
 			goto err;
 	}
 
+	for (i = 0; i < ARRAY_SIZE(bl_info.space); i++)
+		bl_info.reserved_total += bl_info.space[i].size;
+
 	DRM_INFO("VGT balloon successfully\n");
 	return 0;
 
diff --git a/drivers/gpu/drm/i915/i915_vgpu.h b/drivers/gpu/drm/i915/i915_vgpu.h
index 3c3b2d2..e776580 100644
--- a/drivers/gpu/drm/i915/i915_vgpu.h
+++ b/drivers/gpu/drm/i915/i915_vgpu.h
@@ -29,5 +29,7 @@
 void i915_check_vgpu(struct drm_i915_private *dev_priv);
 int intel_vgt_balloon(struct drm_i915_private *dev_priv);
 void intel_vgt_deballoon(struct drm_i915_private *dev_priv);
+size_t intel_vgt_reserved_size_by_balloon(
+		struct drm_i915_private *dev_priv);
 
 #endif /* _I915_VGPU_H_ */
-- 
1.9.1