kernel/qxl-fixes.patch

From c463b4ad6b2ac5a40c959e6c636eafc7edb1a63b Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Wed, 6 Sep 2017 11:31:51 +0200
Subject: qxl: fix primary surface handling

The atomic conversion of the qxl driver didn't got the primary surface
handling completely right.  It works in the common simple cases, but
fails for example when changing the display resolution using xrandr or
in multihead setups.

The rules are simple:  There is one primary surface.  Before defining a
new one you have to destroy the old one.

This patch makes qxl_primary_atomic_update() destroy the primary surface
before defining a new one.  It fixes is_primary flag updates.  It adds
is_primary checks so we don't try to update the primary surface in case
it already has the state we want it being in.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/qxl/qxl_display.c | 34 +++++++++++++++++++---------------
 1 file changed, 19 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c
index 03fe182..7babdd8f 100644
--- a/drivers/gpu/drm/qxl/qxl_display.c
+++ b/drivers/gpu/drm/qxl/qxl_display.c
@@ -512,23 +512,25 @@ static void qxl_primary_atomic_update(struct drm_plane *plane,
 	    .y2 = qfb->base.height
 	};
 
-	if (!old_state->fb) {
-		qxl_io_log(qdev,
-			   "create primary fb: %dx%d,%d,%d\n",
-			   bo->surf.width, bo->surf.height,
-			   bo->surf.stride, bo->surf.format);
+	if (old_state->fb) {
+		qfb_old = to_qxl_framebuffer(old_state->fb);
+		bo_old = gem_to_qxl_bo(qfb_old->obj);
+	} else {
+		bo_old = NULL;
+	}
 
-		qxl_io_create_primary(qdev, 0, bo);
-		bo->is_primary = true;
+	if (bo == bo_old)
 		return;
 
-	} else {
-		qfb_old = to_qxl_framebuffer(old_state->fb);
-		bo_old = gem_to_qxl_bo(qfb_old->obj);
+	if (bo_old && bo_old->is_primary) {
+		qxl_io_destroy_primary(qdev);
 		bo_old->is_primary = false;
 	}
 
-	bo->is_primary = true;
+	if (!bo->is_primary) {
+		qxl_io_create_primary(qdev, 0, bo);
+		bo->is_primary = true;
+	}
 	qxl_draw_dirty_fb(qdev, qfb, bo, 0, 0, &norect, 1, 1);
 }
 
@@ -537,13 +539,15 @@ static void qxl_primary_atomic_disable(struct drm_plane *plane,
 {
 	struct qxl_device *qdev = plane->dev->dev_private;
 
-	if (old_state->fb)
-	{	struct qxl_framebuffer *qfb =
+	if (old_state->fb) {
+		struct qxl_framebuffer *qfb =
 			to_qxl_framebuffer(old_state->fb);
 		struct qxl_bo *bo = gem_to_qxl_bo(qfb->obj);
 
-		qxl_io_destroy_primary(qdev);
-		bo->is_primary = false;
+		if (bo->is_primary) {
+			qxl_io_destroy_primary(qdev);
+			bo->is_primary = false;
+		}
 	}
 }
 
-- 
cgit v0.12

From 05026e6e19b29104ddba4e8979e6c7af17944695 Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Fri, 15 Sep 2017 12:46:15 +0200
Subject: [testing] qxl: fix pinning

cleanup_fb() unpins the just activated framebuffer instead of the
old one.  Oops.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/qxl/qxl_display.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c
index 7babdd8f..afc2272 100644
--- a/drivers/gpu/drm/qxl/qxl_display.c
+++ b/drivers/gpu/drm/qxl/qxl_display.c
@@ -705,14 +705,15 @@ static void qxl_plane_cleanup_fb(struct drm_plane *plane,
 	struct drm_gem_object *obj;
 	struct qxl_bo *user_bo;
 
-	if (!plane->state->fb) {
-		/* we never executed prepare_fb, so there's nothing to
+	if (!old_state->fb) {
+		/*
+		 * we never executed prepare_fb, so there's nothing to
 		 * unpin.
 		 */
 		return;
 	}
 
-	obj = to_qxl_framebuffer(plane->state->fb)->obj;
+	obj = to_qxl_framebuffer(old_state->fb)->obj;
 	user_bo = gem_to_qxl_bo(obj);
 	qxl_bo_unpin(user_bo);
 }
-- 
cgit v0.12

From 7a39a01887acc66d9b318d5e5898cf00d323eb8f Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Wed, 18 Oct 2017 13:18:40 +0200
Subject: qxl: alloc & use shadow for dumb buffers

This patch changes the way the primary surface is used for dumb
framebuffers.  Instead of configuring the bo itself as primary surface
a shadow bo is created and used instead.  Framebuffers can share the
shadow bo in case they have the same format and resolution.

On atomic plane updates we don't have to update the primary surface in
case we pageflip from one framebuffer to another framebuffer which
shares the same shadow.  This in turn avoids the flicker caused by the
primary-destroy + primary-create cycle, which is very annonying when
running wayland on qxl.

The qxl driver never actually writes to the shadow bo.  It sends qxl
blit commands which update it though, and the spice server might
actually execute them (and thereby write to the shadow) in case the
local rendering is kicked for some reason.  This happens for example in
case qemu is asked to write out a dump of the guest display (screendump
monitor command).

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/qxl/qxl_cmd.c     |  6 ++++-
 drivers/gpu/drm/qxl/qxl_display.c | 49 ++++++++++++++++++++++++++++++++++++---
 drivers/gpu/drm/qxl/qxl_drv.h     |  2 ++
 drivers/gpu/drm/qxl/qxl_dumb.c    |  1 +
 4 files changed, 54 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/qxl/qxl_cmd.c b/drivers/gpu/drm/qxl/qxl_cmd.c
index 74fc936..3eb9208 100644
--- a/drivers/gpu/drm/qxl/qxl_cmd.c
+++ b/drivers/gpu/drm/qxl/qxl_cmd.c
@@ -388,7 +388,11 @@ void qxl_io_create_primary(struct qxl_device *qdev,
 	create->width = bo->surf.width;
 	create->height = bo->surf.height;
 	create->stride = bo->surf.stride;
-	create->mem = qxl_bo_physical_address(qdev, bo, offset);
+	if (bo->shadow) {
+		create->mem = qxl_bo_physical_address(qdev, bo->shadow, offset);
+	} else {
+		create->mem = qxl_bo_physical_address(qdev, bo, offset);
+	}

 	QXL_INFO(qdev, "%s: mem = %llx, from %p\n", __func__, create->mem,
 		 bo->kptr);
diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c
index afc2272..da6648e 100644
--- a/drivers/gpu/drm/qxl/qxl_display.c
+++ b/drivers/gpu/drm/qxl/qxl_display.c
@@ -305,7 +305,9 @@ static const struct drm_crtc_funcs qxl_crtc_funcs = {
 void qxl_user_framebuffer_destroy(struct drm_framebuffer *fb)
 {
 	struct qxl_framebuffer *qxl_fb = to_qxl_framebuffer(fb);
+	struct qxl_bo *bo = gem_to_qxl_bo(qxl_fb->obj);

+	WARN_ON(bo->shadow);
 	drm_gem_object_unreference_unlocked(qxl_fb->obj);
 	drm_framebuffer_cleanup(fb);
 	kfree(qxl_fb);
@@ -511,6 +513,7 @@ static void qxl_primary_atomic_update(struct drm_plane *plane,
 	    .x2 = qfb->base.width,
 	    .y2 = qfb->base.height
 	};
+	bool same_shadow = false;

 	if (old_state->fb) {
 		qfb_old = to_qxl_framebuffer(old_state->fb);
@@ -522,15 +525,23 @@ static void qxl_primary_atomic_update(struct drm_plane *plane,
 	if (bo == bo_old)
 		return;

+	if (bo_old && bo_old->shadow && bo->shadow &&
+	    bo_old->shadow == bo->shadow) {
+		same_shadow = true;
+	}
+
 	if (bo_old && bo_old->is_primary) {
-		qxl_io_destroy_primary(qdev);
+		if (!same_shadow)
+			qxl_io_destroy_primary(qdev);
 		bo_old->is_primary = false;
 	}

 	if (!bo->is_primary) {
-		qxl_io_create_primary(qdev, 0, bo);
+		if (!same_shadow)
+			qxl_io_create_primary(qdev, 0, bo);
 		bo->is_primary = true;
 	}
+
 	qxl_draw_dirty_fb(qdev, qfb, bo, 0, 0, &norect, 1, 1);
 }

@@ -682,8 +693,9 @@ void qxl_cursor_atomic_disable(struct drm_plane *plane,
 int qxl_plane_prepare_fb(struct drm_plane *plane,
 			 struct drm_plane_state *new_state)
 {
+	struct qxl_device *qdev = plane->dev->dev_private;
 	struct drm_gem_object *obj;
-	struct qxl_bo *user_bo;
+	struct qxl_bo *user_bo, *old_bo = NULL;
 	int ret;

 	if (!new_state->fb)
@@ -692,6 +704,32 @@ int qxl_plane_prepare_fb(struct drm_plane *plane,
 	obj = to_qxl_framebuffer(new_state->fb)->obj;
 	user_bo = gem_to_qxl_bo(obj);

+	if (plane->type == DRM_PLANE_TYPE_PRIMARY &&
+	    user_bo->is_dumb && !user_bo->shadow) {
+		if (plane->state->fb) {
+			obj = to_qxl_framebuffer(plane->state->fb)->obj;
+			old_bo = gem_to_qxl_bo(obj);
+		}
+		if (old_bo && old_bo->shadow &&
+		    user_bo->gem_base.size == old_bo->gem_base.size &&
+		    plane->state->crtc     == new_state->crtc &&
+		    plane->state->crtc_w   == new_state->crtc_w &&
+		    plane->state->crtc_h   == new_state->crtc_h &&
+		    plane->state->src_x    == new_state->src_x &&
+		    plane->state->src_y    == new_state->src_y &&
+		    plane->state->src_w    == new_state->src_w &&
+		    plane->state->src_h    == new_state->src_h &&
+		    plane->state->rotation == new_state->rotation &&
+		    plane->state->zpos     == new_state->zpos) {
+			drm_gem_object_get(&old_bo->shadow->gem_base);
+			user_bo->shadow = old_bo->shadow;
+		} else {
+			qxl_bo_create(qdev, user_bo->gem_base.size,
+				      true, true, QXL_GEM_DOMAIN_VRAM, NULL,
+				      &user_bo->shadow);
+		}
+	}
+
 	ret = qxl_bo_pin(user_bo, QXL_GEM_DOMAIN_CPU, NULL);
 	if (ret)
 		return ret;
@@ -716,6 +754,11 @@ static void qxl_plane_cleanup_fb(struct drm_plane *plane,
 	obj = to_qxl_framebuffer(old_state->fb)->obj;
 	user_bo = gem_to_qxl_bo(obj);
 	qxl_bo_unpin(user_bo);
+
+	if (user_bo->shadow && !user_bo->is_primary) {
+		drm_gem_object_put_unlocked(&user_bo->shadow->gem_base);
+		user_bo->shadow = NULL;
+	}
 }

 static const uint32_t qxl_cursor_plane_formats[] = {
diff --git a/drivers/gpu/drm/qxl/qxl_drv.h b/drivers/gpu/drm/qxl/qxl_drv.h
index 3591d23..b5e9dc6 100644
--- a/drivers/gpu/drm/qxl/qxl_drv.h
+++ b/drivers/gpu/drm/qxl/qxl_drv.h
@@ -112,6 +112,8 @@ struct qxl_bo {
 	/* Constant after initialization */
 	struct drm_gem_object		gem_base;
 	bool is_primary; /* is this now a primary surface */
+	bool is_dumb;
+	struct qxl_bo *shadow;
 	bool hw_surf_alloc;
 	struct qxl_surface surf;
 	uint32_t surface_id;
diff --git a/drivers/gpu/drm/qxl/qxl_dumb.c b/drivers/gpu/drm/qxl/qxl_dumb.c
index 5e65d5d..11085ab 100644
--- a/drivers/gpu/drm/qxl/qxl_dumb.c
+++ b/drivers/gpu/drm/qxl/qxl_dumb.c
@@ -63,6 +63,7 @@ int qxl_mode_dumb_create(struct drm_file *file_priv,
 					      &handle);
 	if (r)
 		return r;
+	qobj->is_dumb = true;
 	args->pitch = pitch;
 	args->handle = handle;
 	return 0;
-- 
2.13.5