loader: Don't load nouveau GL on nvidia kmd

The vulkan driver already has a check for this. This prevents the GL
driver from loading too.

Reviewed-by: Karol Herbst <kherbst@redhat.com>
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/13484
Fixes: e99446fc ("egl: Add EGL_EXT_device_query_name and EGL_EXT_device_persistent_id")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36449>

src/loader/loader.c

@@ -47,6 +47,7 @@
 #include <GL/gl.h>
 #include "mesa_interface.h"
 #include "loader.h"
+#include "util/drm_is_nouveau.h"
 #include "util/libdrm.h"
 #include "util/os_file.h"
 #include "util/os_misc.h"
@@ -138,6 +139,10 @@ iris_predicate(int fd, const char *driver)
 bool
 nouveau_zink_predicate(int fd, const char *driver)
 {
+   /* Never load on nv proprietary driver */
+   if (!drm_fd_is_nouveau(fd))
+      return false;
+
 #if !defined(HAVE_NVK) || !defined(HAVE_ZINK)
    if (!strcmp(driver, "zink"))
       return false;

src/nouveau/vulkan/nvkmd/nouveau/nvkmd_nouveau_pdev.c

@@ -7,6 +7,7 @@
 
 #include "nouveau_device.h"
 #include "util/os_misc.h"
+#include "util/drm_is_nouveau.h"
 #include "vk_log.h"
 
 #include <fcntl.h>
@@ -21,15 +22,7 @@ drm_device_is_nouveau(const char *path)
    if (fd < 0)
       return false;
 
-   drmVersionPtr ver = drmGetVersion(fd);
+   const bool is_nouveau = drm_fd_is_nouveau(fd);
-   if (!ver) {
-      close(fd);
-      return false;
-   }
-
-   const bool is_nouveau = !strncmp("nouveau", ver->name, ver->name_len);
-
-   drmFreeVersion(ver);
    close(fd);
 
    return is_nouveau;

src/util/drm_is_nouveau.h

@@ -0,0 +1,18 @@
+#ifndef DRM_IS_NOUVEAU
+#define DRM_IS_NOUVEAU
+
+#include "util/libdrm.h"
+
+static inline bool
+drm_fd_is_nouveau(int fd)
+{
+   drmVersionPtr ver = drmGetVersion(fd);
+   if (!ver) {
+      return false;
+   }
+   const bool is_nouveau = !strncmp("nouveau", ver->name, ver->name_len);
+   drmFreeVersion(ver);
+   return is_nouveau;
+}
+
+#endif