[Mesa-dev] [PATCH] egl/wayland: Don't use dmabuf with no modifiers

[Daniel Stone]

The dmabuf interface requires a valid modifier to be sent. If we don't
explicitly get a modifier from the driver, we can't know what to send;
it must be inferred from legacy side-channels (or assumed to linear, if
none exists).

If we have no modifier, then we can only have a single-plane format
anyway, so fall back to the old wl_drm buffer import path.

Fixes: a65db0ad1c ("st/dri: don't expose modifiers in EGL if the driver doesn't implement them")
Reported-by: Andy Furniss <adf.lists at gmail.com>
Cc: Marek Olšák <marek.olsak at amd.com>
---
 src/egl/drivers/dri2/platform_wayland.c | 45 +++++++++++++++++++++++----------
 1 file changed, 32 insertions(+), 13 deletions(-)

diff --git a/src/egl/drivers/dri2/platform_wayland.c b/src/egl/drivers/dri2/platform_wayland.c
index 011dddfabf..b2c41507d1 100644
--- a/src/egl/drivers/dri2/platform_wayland.c
+++ b/src/egl/drivers/dri2/platform_wayland.c
@@ -678,23 +678,42 @@ create_wl_buffer(struct dri2_egl_display *dri2_dpy,
                  __DRIimage *image)
 {
    struct wl_buffer *ret;
+   GLboolean query;
    int width, height, fourcc, num_planes;
+   uint64_t modifier;
+
+   query = dri2_dpy->image->queryImage(image, __DRI_IMAGE_ATTRIB_WIDTH, &width);
+   query &= dri2_dpy->image->queryImage(image, __DRI_IMAGE_ATTRIB_HEIGHT,
+                                        &height);
+   query &= dri2_dpy->image->queryImage(image, __DRI_IMAGE_ATTRIB_FOURCC,
+                                        &fourcc);
+   if (!query)
+      return NULL;
 
-   dri2_dpy->image->queryImage(image, __DRI_IMAGE_ATTRIB_WIDTH, &width);
-   dri2_dpy->image->queryImage(image, __DRI_IMAGE_ATTRIB_HEIGHT, &height);
-   dri2_dpy->image->queryImage(image, __DRI_IMAGE_ATTRIB_FOURCC, &fourcc);
-   dri2_dpy->image->queryImage(image, __DRI_IMAGE_ATTRIB_NUM_PLANES,
-                               &num_planes);
+   query = dri2_dpy->image->queryImage(image, __DRI_IMAGE_ATTRIB_NUM_PLANES,
+                                       &num_planes);
+   if (!query)
+      num_planes = 1;
 
-   if (dri2_dpy->wl_dmabuf && dri2_dpy->image->base.version >= 15) {
-      struct zwp_linux_buffer_params_v1 *params;
+   modifier = DRM_FORMAT_MOD_INVALID;
+   if (dri2_dpy->image->base.version >= 15) {
       int mod_hi, mod_lo;
-      int i;
 
-      dri2_dpy->image->queryImage(image, __DRI_IMAGE_ATTRIB_MODIFIER_UPPER,
-                                  &mod_hi);
-      dri2_dpy->image->queryImage(image, __DRI_IMAGE_ATTRIB_MODIFIER_LOWER,
-                                  &mod_lo);
+      query = dri2_dpy->image->queryImage(image,
+                                          __DRI_IMAGE_ATTRIB_MODIFIER_UPPER,
+                                          &mod_hi);
+      query &= dri2_dpy->image->queryImage(image,
+                                           __DRI_IMAGE_ATTRIB_MODIFIER_LOWER,
+                                           &mod_lo);
+      if (query) {
+         modifier = (uint64_t) mod_hi << 32;
+         modifier |= (uint64_t) (mod_lo & 0xffffffff);
+      }
+   }
+
+   if (dri2_dpy->wl_dmabuf && modifier != DRM_FORMAT_MOD_INVALID) {
+      struct zwp_linux_buffer_params_v1 *params;
+      int i;
 
       /* We don't need a wrapper for wl_dmabuf objects, because we have to
        * create the intermediate params object; we can set the queue on this,
@@ -725,7 +744,7 @@ create_wl_buffer(struct dri2_egl_display *dri2_dpy,
             dri2_dpy->image->destroyImage(p_image);
 
          zwp_linux_buffer_params_v1_add(params, fd, i, offset, stride,
-                                        mod_hi, mod_lo);
+                                        modifier >> 32, modifier & 0xffffffff);
          close(fd);
       }
 
-- 
2.14.2