vmwgfx: Clip cliprects against screen boundaries in present and dirty

Signed-off-by: Jakob Bornecrantz <jakob@vmware.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/vmwgfx/vmwgfx_kms.c

@@ -31,6 +31,44 @@
 /* Might need a hrtimer here? */
 #define VMWGFX_PRESENT_RATE ((HZ / 60 > 0) ? HZ / 60 : 1)
 
+
+struct vmw_clip_rect {
+	int x1, x2, y1, y2;
+};
+
+/**
+ * Clip @num_rects number of @rects against @clip storing the
+ * results in @out_rects and the number of passed rects in @out_num.
+ */
+void vmw_clip_cliprects(struct drm_clip_rect *rects,
+			int num_rects,
+			struct vmw_clip_rect clip,
+			SVGASignedRect *out_rects,
+			int *out_num)
+{
+	int i, k;
+
+	for (i = 0, k = 0; i < num_rects; i++) {
+		int x1 = max_t(int, clip.x1, rects[i].x1);
+		int y1 = max_t(int, clip.y1, rects[i].y1);
+		int x2 = min_t(int, clip.x2, rects[i].x2);
+		int y2 = min_t(int, clip.y2, rects[i].y2);
+
+		if (x1 >= x2)
+			continue;
+		if (y1 >= y2)
+			continue;
+
+		out_rects[k].left   = x1;
+		out_rects[k].top    = y1;
+		out_rects[k].right  = x2;
+		out_rects[k].bottom = y2;
+		k++;
+	}
+
+	*out_num = k;
+}
+
 void vmw_display_unit_cleanup(struct vmw_display_unit *du)
 {
 	if (du->cursor_surface)
@@ -386,8 +424,9 @@ static int do_surface_dirty_sou(struct vmw_private *dev_priv,
 				struct drm_clip_rect *clips,
 				unsigned num_clips, int inc)
 {
-	struct drm_clip_rect *clips_ptr;
 	struct vmw_display_unit *units[VMWGFX_NUM_DISPLAY_UNITS];
+	struct drm_clip_rect *clips_ptr;
+	struct drm_clip_rect *tmp;
 	struct drm_crtc *crtc;
 	size_t fifo_size;
 	int i, num_units;
@@ -400,7 +439,6 @@ static int do_surface_dirty_sou(struct vmw_private *dev_priv,
 	} *cmd;
 	SVGASignedRect *blits;
 
-
 	num_units = 0;
 	list_for_each_entry(crtc, &dev_priv->dev->mode_config.crtc_list,
 			    head) {
@@ -411,13 +449,24 @@ static int do_surface_dirty_sou(struct vmw_private *dev_priv,
 
 	BUG_ON(!clips || !num_clips);
 
+	tmp = kzalloc(sizeof(*tmp) * num_clips, GFP_KERNEL);
+	if (unlikely(tmp == NULL)) {
+		DRM_ERROR("Temporary cliprect memory alloc failed.\n");
+		return -ENOMEM;
+	}
+
 	fifo_size = sizeof(*cmd) + sizeof(SVGASignedRect) * num_clips;
 	cmd = kzalloc(fifo_size, GFP_KERNEL);
 	if (unlikely(cmd == NULL)) {
 		DRM_ERROR("Temporary fifo memory alloc failed.\n");
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto out_free_tmp;
 	}
 
+	/* setup blits pointer */
+	blits = (SVGASignedRect *)&cmd[1];
+
+	/* initial clip region */
 	left = clips->x1;
 	right = clips->x2;
 	top = clips->y1;
@@ -443,45 +492,60 @@ static int do_surface_dirty_sou(struct vmw_private *dev_priv,
 	cmd->body.srcRect.bottom = bottom;
 
 	clips_ptr = clips;
-	blits = (SVGASignedRect *)&cmd[1];
 	for (i = 0; i < num_clips; i++, clips_ptr += inc) {
-		blits[i].left   = clips_ptr->x1 - left;
-		blits[i].right  = clips_ptr->x2 - left;
-		blits[i].top    = clips_ptr->y1 - top;
-		blits[i].bottom = clips_ptr->y2 - top;
+		tmp[i].x1 = clips_ptr->x1 - left;
+		tmp[i].x2 = clips_ptr->x2 - left;
+		tmp[i].y1 = clips_ptr->y1 - top;
+		tmp[i].y2 = clips_ptr->y2 - top;
 	}
 
 	/* do per unit writing, reuse fifo for each */
 	for (i = 0; i < num_units; i++) {
 		struct vmw_display_unit *unit = units[i];
-		int clip_x1 = left - unit->crtc.x;
-		int clip_y1 = top - unit->crtc.y;
-		int clip_x2 = right - unit->crtc.x;
-		int clip_y2 = bottom - unit->crtc.y;
+		struct vmw_clip_rect clip;
+		int num;
+
+		clip.x1 = left - unit->crtc.x;
+		clip.y1 = top - unit->crtc.y;
+		clip.x2 = right - unit->crtc.x;
+		clip.y2 = bottom - unit->crtc.y;
 
 		/* skip any crtcs that misses the clip region */
-		if (clip_x1 >= unit->crtc.mode.hdisplay ||
-		    clip_y1 >= unit->crtc.mode.vdisplay ||
-		    clip_x2 <= 0 || clip_y2 <= 0)
+		if (clip.x1 >= unit->crtc.mode.hdisplay ||
+		    clip.y1 >= unit->crtc.mode.vdisplay ||
+		    clip.x2 <= 0 || clip.y2 <= 0)
 			continue;
 
+		/*
+		 * In order for the clip rects to be correctly scaled
+		 * the src and dest rects needs to be the same size.
+		 */
+		cmd->body.destRect.left = clip.x1;
+		cmd->body.destRect.right = clip.x2;
+		cmd->body.destRect.top = clip.y1;
+		cmd->body.destRect.bottom = clip.y2;
+
+		/* create a clip rect of the crtc in dest coords */
+		clip.x2 = unit->crtc.mode.hdisplay - clip.x1;
+		clip.y2 = unit->crtc.mode.vdisplay - clip.y1;
+		clip.x1 = 0 - clip.x1;
+		clip.y1 = 0 - clip.y1;
+
 		/* need to reset sid as it is changed by execbuf */
 		cmd->body.srcImage.sid = cpu_to_le32(framebuffer->user_handle);
-
 		cmd->body.destScreenId = unit->unit;
 
-		/*
-		 * The blit command is a lot more resilient then the
-		 * readback command when it comes to clip rects. So its
-		 * okay to go out of bounds.
-		 */
+		/* clip and write blits to cmd stream */
+		vmw_clip_cliprects(tmp, num_clips, clip, blits, &num);
 
-		cmd->body.destRect.left = clip_x1;
-		cmd->body.destRect.right = clip_x2;
-		cmd->body.destRect.top = clip_y1;
-		cmd->body.destRect.bottom = clip_y2;
+		/* if no cliprects hit skip this */
+		if (num == 0)
+			continue;
 
 
+		/* recalculate package length */
+		fifo_size = sizeof(*cmd) + sizeof(SVGASignedRect) * num;
+		cmd->header.size = cpu_to_le32(fifo_size - sizeof(cmd->header));
 		ret = vmw_execbuf_process(file_priv, dev_priv, NULL, cmd,
 					  fifo_size, 0, NULL);
 
@@ -489,7 +553,10 @@ static int do_surface_dirty_sou(struct vmw_private *dev_priv,
 			break;
 	}
 
+
 	kfree(cmd);
+out_free_tmp:
+	kfree(tmp);
 
 	return ret;
 }
@@ -795,6 +862,7 @@ static int do_dmabuf_dirty_sou(struct drm_file *file_priv,
 			int clip_y1 = clips_ptr->y1 - unit->crtc.y;
 			int clip_x2 = clips_ptr->x2 - unit->crtc.x;
 			int clip_y2 = clips_ptr->y2 - unit->crtc.y;
+			int move_x, move_y;
 
 			/* skip any crtcs that misses the clip region */
 			if (clip_x1 >= unit->crtc.mode.hdisplay ||
@@ -802,12 +870,21 @@ static int do_dmabuf_dirty_sou(struct drm_file *file_priv,
 			    clip_x2 <= 0 || clip_y2 <= 0)
 				continue;
 
+			/* clip size to crtc size */
+			clip_x2 = min_t(int, clip_x2, unit->crtc.mode.hdisplay);
+			clip_y2 = min_t(int, clip_y2, unit->crtc.mode.vdisplay);
+
+			/* translate both src and dest to bring clip into screen */
+			move_x = min_t(int, clip_x1, 0);
+			move_y = min_t(int, clip_y1, 0);
+
+			/* actual translate done here */
 			blits[hit_num].header = SVGA_CMD_BLIT_GMRFB_TO_SCREEN;
 			blits[hit_num].body.destScreenId = unit->unit;
-			blits[hit_num].body.srcOrigin.x = clips_ptr->x1;
-			blits[hit_num].body.srcOrigin.y = clips_ptr->y1;
-			blits[hit_num].body.destRect.left = clip_x1;
-			blits[hit_num].body.destRect.top = clip_y1;
+			blits[hit_num].body.srcOrigin.x = clips_ptr->x1 - move_x;
+			blits[hit_num].body.srcOrigin.y = clips_ptr->y1 - move_y;
+			blits[hit_num].body.destRect.left = clip_x1 - move_x;
+			blits[hit_num].body.destRect.top = clip_y1 - move_y;
 			blits[hit_num].body.destRect.right = clip_x2;
 			blits[hit_num].body.destRect.bottom = clip_y2;
 			hit_num++;
@@ -1094,6 +1171,7 @@ int vmw_kms_present(struct vmw_private *dev_priv,
 		    uint32_t num_clips)
 {
 	struct vmw_display_unit *units[VMWGFX_NUM_DISPLAY_UNITS];
+	struct drm_clip_rect *tmp;
 	struct drm_crtc *crtc;
 	size_t fifo_size;
 	int i, k, num_units;
@@ -1116,11 +1194,18 @@ int vmw_kms_present(struct vmw_private *dev_priv,
 	BUG_ON(surface == NULL);
 	BUG_ON(!clips || !num_clips);
 
+	tmp = kzalloc(sizeof(*tmp) * num_clips, GFP_KERNEL);
+	if (unlikely(tmp == NULL)) {
+		DRM_ERROR("Temporary cliprect memory alloc failed.\n");
+		return -ENOMEM;
+	}
+
 	fifo_size = sizeof(*cmd) + sizeof(SVGASignedRect) * num_clips;
 	cmd = kmalloc(fifo_size, GFP_KERNEL);
 	if (unlikely(cmd == NULL)) {
 		DRM_ERROR("Failed to allocate temporary fifo memory.\n");
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto out_free_tmp;
 	}
 
 	left = clips->x;
@@ -1138,50 +1223,66 @@ int vmw_kms_present(struct vmw_private *dev_priv,
 	/* only need to do this once */
 	memset(cmd, 0, fifo_size);
 	cmd->header.id = cpu_to_le32(SVGA_3D_CMD_BLIT_SURFACE_TO_SCREEN);
-	cmd->header.size = cpu_to_le32(fifo_size - sizeof(cmd->header));
+
+	blits = (SVGASignedRect *)&cmd[1];
 
 	cmd->body.srcRect.left = left;
 	cmd->body.srcRect.right = right;
 	cmd->body.srcRect.top = top;
 	cmd->body.srcRect.bottom = bottom;
 
-	blits = (SVGASignedRect *)&cmd[1];
 	for (i = 0; i < num_clips; i++) {
-		blits[i].left   = clips[i].x - left;
-		blits[i].right  = clips[i].x + clips[i].w - left;
-		blits[i].top    = clips[i].y - top;
-		blits[i].bottom = clips[i].y + clips[i].h - top;
+		tmp[i].x1 = clips[i].x - left;
+		tmp[i].x2 = clips[i].x + clips[i].w - left;
+		tmp[i].y1 = clips[i].y - top;
+		tmp[i].y2 = clips[i].y + clips[i].h - top;
 	}
 
 	for (k = 0; k < num_units; k++) {
 		struct vmw_display_unit *unit = units[k];
-		int clip_x1 = left + destX - unit->crtc.x;
-		int clip_y1 = top + destY - unit->crtc.y;
-		int clip_x2 = right + destX - unit->crtc.x;
-		int clip_y2 = bottom + destY - unit->crtc.y;
+		struct vmw_clip_rect clip;
+		int num;
+
+		clip.x1 = left + destX - unit->crtc.x;
+		clip.y1 = top + destY - unit->crtc.y;
+		clip.x2 = right + destX - unit->crtc.x;
+		clip.y2 = bottom + destY - unit->crtc.y;
 
 		/* skip any crtcs that misses the clip region */
-		if (clip_x1 >= unit->crtc.mode.hdisplay ||
-		    clip_y1 >= unit->crtc.mode.vdisplay ||
-		    clip_x2 <= 0 || clip_y2 <= 0)
+		if (clip.x1 >= unit->crtc.mode.hdisplay ||
+		    clip.y1 >= unit->crtc.mode.vdisplay ||
+		    clip.x2 <= 0 || clip.y2 <= 0)
 			continue;
 
+		/*
+		 * In order for the clip rects to be correctly scaled
+		 * the src and dest rects needs to be the same size.
+		 */
+		cmd->body.destRect.left = clip.x1;
+		cmd->body.destRect.right = clip.x2;
+		cmd->body.destRect.top = clip.y1;
+		cmd->body.destRect.bottom = clip.y2;
+
+		/* create a clip rect of the crtc in dest coords */
+		clip.x2 = unit->crtc.mode.hdisplay - clip.x1;
+		clip.y2 = unit->crtc.mode.vdisplay - clip.y1;
+		clip.x1 = 0 - clip.x1;
+		clip.y1 = 0 - clip.y1;
+
 		/* need to reset sid as it is changed by execbuf */
 		cmd->body.srcImage.sid = sid;
-
 		cmd->body.destScreenId = unit->unit;
 
-		/*
-		 * The blit command is a lot more resilient then the
-		 * readback command when it comes to clip rects. So its
-		 * okay to go out of bounds.
-		 */
+		/* clip and write blits to cmd stream */
+		vmw_clip_cliprects(tmp, num_clips, clip, blits, &num);
 
-		cmd->body.destRect.left = clip_x1;
-		cmd->body.destRect.right = clip_x2;
-		cmd->body.destRect.top = clip_y1;
-		cmd->body.destRect.bottom = clip_y2;
+		/* if no cliprects hit skip this */
+		if (num == 0)
+			continue;
 
+		/* recalculate package length */
+		fifo_size = sizeof(*cmd) + sizeof(SVGASignedRect) * num;
+		cmd->header.size = cpu_to_le32(fifo_size - sizeof(cmd->header));
 		ret = vmw_execbuf_process(file_priv, dev_priv, NULL, cmd,
 					  fifo_size, 0, NULL);
 
@@ -1190,6 +1291,8 @@ int vmw_kms_present(struct vmw_private *dev_priv,
 	}
 
 	kfree(cmd);
+out_free_tmp:
+	kfree(tmp);
 
 	return ret;
 }