egl: allow INVALID format for linux_dmabuf

As per
https://gitlab.freedesktop.org/wayland/wayland-protocols/commit/fb9b2a87317c77e26283da5f6c9559d709f6fdcd,
the compositor may advertise DRM_FORMAT_MOD_INVALID as a supported
modifier. This patch makes mesa recognize this fact and allow
linux_dmabuf usage with the INVALID modifier in this case.

In case the driver doesn't support modifiers, we can still use
linux-dmabuf protocol instead of the legacy wl_drm interface to create
wl_buffers. This will help compositors to handle these buffers better.

In this commit, the INVALID modifier is allowed to be added to the list
of supported modifiers, and create_wl_buffer will be able to use
linux_dmabuf with an INVALID modifier if the compositor advertised it as
supported.

Signed-off-by: Ivan Molodetskikh <yalterz@gmail.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/2147>
(cherry picked from commit c376865f5eeca535c4aa8e33bcf166052c1ce2f2)

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4869>

1 files changed, 24 insertions, 5 deletions

diff --git a/src/egl/drivers/dri2/platform_wayland.c b/src/egl/drivers/dri2/platform_wayland.c
index 71bcb04a77b..324ac2357da 100644
--- a/src/egl/drivers/dri2/platform_wayland.c
+++ b/src/egl/drivers/dri2/platform_wayland.c
@@ -522,6 +522,13 @@ get_back_bo(struct dri2_egl_surface *dri2_surf)
    modifiers = u_vector_tail(&dri2_dpy->wl_modifiers[visual_idx]);
    num_modifiers = u_vector_length(&dri2_dpy->wl_modifiers[visual_idx]);
 
+   if (num_modifiers == 1 && modifiers[0] == DRM_FORMAT_MOD_INVALID) {
+      /* For the purposes of this function, an INVALID modifier on its own
+       * means the modifiers aren't supported.
+       */
+      num_modifiers = 0;
+   }
+
    /* Substitute dri image format if server does not support original format */
    if (!BITSET_TEST(dri2_dpy->formats, visual_idx))
       linear_dri_image_format = dri2_wl_visuals[visual_idx].alt_dri_image_format;
@@ -917,7 +924,23 @@ create_wl_buffer(struct dri2_egl_display *dri2_dpy,
       }
    }
 
-   if (dri2_dpy->wl_dmabuf && modifier != DRM_FORMAT_MOD_INVALID) {
+   bool supported_modifier = false;
+   if (modifier != DRM_FORMAT_MOD_INVALID) {
+      supported_modifier = true;
+   } else {
+      int visual_idx = dri2_wl_visual_idx_from_fourcc(fourcc);
+      assert(visual_idx != -1);
+
+      uint64_t *mod;
+      u_vector_foreach(mod, &dri2_dpy->wl_modifiers[visual_idx]) {
+         if (*mod == DRM_FORMAT_MOD_INVALID) {
+            supported_modifier = true;
+            break;
+         }
+      }
+   }
+
+   if (dri2_dpy->wl_dmabuf && supported_modifier) {
       struct zwp_linux_buffer_params_v1 *params;
       int i;
 
@@ -1290,10 +1313,6 @@ dmabuf_handle_modifier(void *data, struct zwp_linux_dmabuf_v1 *dmabuf,
    if (visual_idx == -1)
       return;
 
-   if (modifier_hi == (DRM_FORMAT_MOD_INVALID >> 32) &&
-       modifier_lo == (DRM_FORMAT_MOD_INVALID & 0xffffffff))
-      return;
-
    BITSET_SET(dri2_dpy->formats, visual_idx);
 
    mod = u_vector_add(&dri2_dpy->wl_modifiers[visual_idx]);