From 582b2d345abaa0e313cf16c902e602084ea59551 Mon Sep 17 00:00:00 2001
From: Erik Kurzinger <ekurzinger@nvidia.com>
Date: Tue, 23 Nov 2021 14:15:14 -0500
Subject: [PATCH] egl-wayland: retrieve DRM device name before acquiring API
lock
wlEglBindDisplaysHook acquires the external API lock before calling
wl_eglstream_display_bind, which in turn calls wl_drm_display_bind. That
function calls back into EGL to query the DRM device associated with the
given EGLDisplay.
Normally this is not a problem since the EGLDisplay passed to
eglBindWaylandDisplayWL will be an internal EGL_PLATFORM_DEVICE handle.
However, some applications, notably anything WebKit-based, will instead
pass in an external EGL_PLATFORM_WAYLAND handle. This means that the
eglQueryDisplayAttrib call by wl_drm_display_bind will require EGL to
call back into the egl-wayland library to look up the internal handle.
This is done by wlEglGetInternalHandleExport, which will attempt to
acquire the external API lock a second time, which will fail.
To avoid this, add a new function to wayland-drm.c which will retrieve
the DRM device name for the given EGLDisplay. wlEglBindDisplaysHook will
call this *before* acquiring the external API lock, and then pass it to
wl_drm_display_bind via wl_eglstream_display_bind so it can be saved in
the wl_eglstream_display struct.
---
include/wayland-drm.h | 7 ++++++-
include/wayland-eglstream-server.h | 3 ++-
src/wayland-drm.c | 33 +++++++++++++++---------------
src/wayland-egldisplay.c | 8 +++++---
src/wayland-eglstream-server.c | 5 +++--
5 files changed, 32 insertions(+), 24 deletions(-)
diff --git a/include/wayland-drm.h b/include/wayland-drm.h
index be363c6..84d0f11 100644
--- a/include/wayland-drm.h
+++ b/include/wayland-drm.h
@@ -23,9 +23,14 @@
#ifndef WAYLAND_DRM_H
#define WAYLAND_DRM_H
+extern const char *
+wl_drm_get_dev_name(const WlEglPlatformData *data,
+ EGLDisplay dpy);
+
extern EGLBoolean
wl_drm_display_bind(struct wl_display *display,
- struct wl_eglstream_display *wlStreamDpy);
+ struct wl_eglstream_display *wlStreamDpy,
+ const char *dev_name);
extern void
wl_drm_display_unbind(struct wl_eglstream_display *wlStreamDpy);
diff --git a/include/wayland-eglstream-server.h b/include/wayland-eglstream-server.h
index 76e772c..0f7d477 100644
--- a/include/wayland-eglstream-server.h
+++ b/include/wayland-eglstream-server.h
@@ -49,7 +49,8 @@ EGLBoolean
wl_eglstream_display_bind(WlEglPlatformData *data,
struct wl_display *wlDisplay,
EGLDisplay eglDisplay,
- const char *exts);
+ const char *exts,
+ const char *dev_name);
/*
* wl_eglstream_display_unbind()
diff --git a/src/wayland-drm.c b/src/wayland-drm.c
index aa6de23..a08d82f 100644
--- a/src/wayland-drm.c
+++ b/src/wayland-drm.c
@@ -152,37 +152,36 @@ bind(struct wl_client *client, void *data, uint32_t version, uint32_t id)
wl_resource_post_event(resource, WL_DRM_CAPABILITIES, 0);
}
-EGLBoolean
-wl_drm_display_bind(struct wl_display *display,
- struct wl_eglstream_display *wlStreamDpy)
+const char *
+wl_drm_get_dev_name(const WlEglPlatformData *data,
+ EGLDisplay dpy)
{
- EGLDisplay dpy = wlStreamDpy->eglDisplay;
EGLDeviceEXT egl_dev;
const char *dev_exts;
- const char *dev_name;
- if (!wlStreamDpy->data->egl.queryDisplayAttrib(dpy,
- EGL_DEVICE_EXT,
- (EGLAttribKHR*)&egl_dev)) {
- return EGL_FALSE;
+ if (!data->egl.queryDisplayAttrib(dpy, EGL_DEVICE_EXT,
+ (EGLAttribKHR*)&egl_dev)) {
+ return NULL;
}
-
- dev_exts = wlStreamDpy->data->egl.queryDeviceString(egl_dev,
- EGL_EXTENSIONS);
+ dev_exts = data->egl.queryDeviceString(egl_dev, EGL_EXTENSIONS);
if (!dev_exts) {
- return EGL_FALSE;
+ return NULL;
}
if (!wlEglFindExtension("EGL_EXT_device_drm_render_node", dev_exts)) {
- return EGL_FALSE;
+ return NULL;
}
- dev_name =
- wlStreamDpy->data->egl.queryDeviceString(egl_dev,
- EGL_DRM_RENDER_NODE_FILE_EXT);
+ return data->egl.queryDeviceString(egl_dev, EGL_DRM_RENDER_NODE_FILE_EXT);
+}
+EGLBoolean
+wl_drm_display_bind(struct wl_display *display,
+ struct wl_eglstream_display *wlStreamDpy,
+ const char *dev_name)
+{
if (!dev_name) {
return EGL_FALSE;
}
diff --git a/src/wayland-egldisplay.c b/src/wayland-egldisplay.c
index 8b7394a..d285bf7 100644
--- a/src/wayland-egldisplay.c
+++ b/src/wayland-egldisplay.c
@@ -30,6 +30,7 @@
#include "wayland-eglhandle.h"
#include "wayland-eglutils.h"
#include "wayland-drm-client-protocol.h"
+#include "wayland-drm.h"
#include <string.h>
#include <stdlib.h>
#include <assert.h>
@@ -70,15 +71,16 @@ EGLBoolean wlEglIsValidNativeDisplayExport(void *data, void *nativeDpy)
EGLBoolean wlEglBindDisplaysHook(void *data, EGLDisplay dpy, void *nativeDpy)
{
- /* Retrieve extension string before taking external API lock */
- const char *exts = ((WlEglPlatformData *)data)->egl.queryString(dpy, EGL_EXTENSIONS);
+ /* Retrieve extension string and device name before taking external API lock */
+ const char *exts = ((WlEglPlatformData *)data)->egl.queryString(dpy, EGL_EXTENSIONS),
+ *dev_name = wl_drm_get_dev_name(data, dpy);
EGLBoolean res = EGL_FALSE;
wlExternalApiLock();
res = wl_eglstream_display_bind((WlEglPlatformData *)data,
(struct wl_display *)nativeDpy,
- dpy, exts);
+ dpy, exts, dev_name);
wlExternalApiUnlock();
diff --git a/src/wayland-eglstream-server.c b/src/wayland-eglstream-server.c
index b1baa08..1dfd7ce 100644
--- a/src/wayland-eglstream-server.c
+++ b/src/wayland-eglstream-server.c
@@ -289,7 +289,8 @@ EGLBoolean
wl_eglstream_display_bind(WlEglPlatformData *data,
struct wl_display *wlDisplay,
EGLDisplay eglDisplay,
- const char *exts)
+ const char *exts,
+ const char *dev_name)
{
struct wl_eglstream_display *wlStreamDpy = NULL;
char *env = NULL;
@@ -355,7 +356,7 @@ wl_eglstream_display_bind(WlEglPlatformData *data,
wl_eglstream_display_global_bind);
/* Failure is not fatal */
- wl_drm_display_bind(wlDisplay, wlStreamDpy);
+ wl_drm_display_bind(wlDisplay, wlStreamDpy, dev_name);
wl_list_insert(&wlStreamDpyList, &wlStreamDpy->link);