KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted

Skip the xarray reservation loop when clearing all memory attributes, as
storing NULL only erases the entry and never needs to allocate, so no
reservation (and no cleanup of a failed one) is required in that case.

Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: David Ballesteros <davimaba.v@proton.me>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com
[sean: split to separate patch]
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 63 insertions, 0 deletions

diff --git a/include/drm/drm_blend.h b/include/drm/drm_blend.h
new file mode 100644
index 000000000..bebbb77a8
--- /dev/null
+++ b/include/drm/drm_blend.h
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2016 Intel Corporation
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission.  The copyright holders make no representations
+ * about the suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#ifndef __DRM_BLEND_H__
+#define __DRM_BLEND_H__
+
+#include <linux/list.h>
+#include <linux/ctype.h>
+#include <drm/drm_mode.h>
+
+#define DRM_MODE_BLEND_PREMULTI		0
+#define DRM_MODE_BLEND_COVERAGE		1
+#define DRM_MODE_BLEND_PIXEL_NONE	2
+
+struct drm_atomic_commit;
+struct drm_crtc;
+struct drm_device;
+struct drm_plane;
+
+static inline bool drm_rotation_90_or_270(unsigned int rotation)
+{
+	return rotation & (DRM_MODE_ROTATE_90 | DRM_MODE_ROTATE_270);
+}
+
+#define DRM_BLEND_ALPHA_OPAQUE		0xffff
+
+int drm_plane_create_alpha_property(struct drm_plane *plane);
+int drm_plane_create_rotation_property(struct drm_plane *plane,
+				       unsigned int rotation,
+				       unsigned int supported_rotations);
+unsigned int drm_rotation_simplify(unsigned int rotation,
+				   unsigned int supported_rotations);
+
+int drm_plane_create_zpos_property(struct drm_plane *plane,
+				   unsigned int zpos,
+				   unsigned int min, unsigned int max);
+int drm_plane_create_zpos_immutable_property(struct drm_plane *plane,
+					     unsigned int zpos);
+int drm_atomic_normalize_zpos(struct drm_device *dev,
+			      struct drm_atomic_commit *state);
+int drm_plane_create_blend_mode_property(struct drm_plane *plane,
+					 unsigned int supported_modes);
+void drm_crtc_attach_background_color_property(struct drm_crtc *crtc);
+#endif