Merge Mesa 17.3.9

Mesa 18.x needs an ld with build-id for at least the intel code
Mesa 18.2 assumes linux only memfd syscalls in intel code

Tested by matthieu@, kettenis@ and myself on a variety of hardware and
architectures. ok kettenis@

6 files changed, 645 insertions, 305 deletions

diff --git a/lib/mesa/src/loader/Makefile.am b/lib/mesa/src/loader/Makefile.am
index 93b46d9e1..74ac6c51e 100644
--- a/lib/mesa/src/loader/Makefile.am
+++ b/lib/mesa/src/loader/Makefile.am
@@ -26,6 +26,8 @@ EXTRA_DIST = SConscript
 noinst_LTLIBRARIES = libloader.la
 
 AM_CPPFLAGS = \
+	-I$(top_builddir)/src/util/ \
+	-DUSE_DRICONF \
 	$(DEFINES) \
 	-I$(top_srcdir)/include \
 	-I$(top_srcdir)/src \
@@ -37,24 +39,12 @@ libloader_la_CPPFLAGS = $(AM_CPPFLAGS)
 libloader_la_SOURCES = $(LOADER_C_FILES)
 libloader_la_LIBADD =
 
-if HAVE_DRICOMMON
-libloader_la_CPPFLAGS += \
-	-I$(top_builddir)/src/mesa/drivers/dri/common/ \
-	-I$(top_srcdir)/src/mesa/drivers/dri/common/ \
-	-I$(top_srcdir)/src/mesa/ \
-	-I$(top_srcdir)/src/mapi/ \
-	-DUSE_DRICONF
-
- libloader_la_LIBADD += \
-	$(top_builddir)/src/mesa/drivers/dri/common/libxmlconfig.la
-
-endif
-
 if HAVE_LIBDRM
 libloader_la_LIBADD += \
 	$(LIBDRM_LIBS)
 endif
 
+if HAVE_PLATFORM_X11
 if HAVE_DRI3
 noinst_LTLIBRARIES += libloader_dri3_helper.la
 
@@ -63,3 +53,4 @@ libloader_dri3_helper_la_SOURCES = \
 	loader_dri3_helper.h
 libloader_dri3_helper_la_LIBADD = $(XCB_DRI3_LIBS)
 endif
+endif
diff --git a/lib/mesa/src/loader/Makefile.in b/lib/mesa/src/loader/Makefile.in
index 4d40b8928..fb418ac81 100644
--- a/lib/mesa/src/loader/Makefile.in
+++ b/lib/mesa/src/loader/Makefile.in
@@ -74,23 +74,14 @@ host_triplet = @host@
 target_triplet = @target@
 DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in \
 	$(srcdir)/Makefile.sources $(top_srcdir)/bin/depcomp
-@HAVE_DRICOMMON_TRUE@am__append_1 = \
-@HAVE_DRICOMMON_TRUE@	-I$(top_builddir)/src/mesa/drivers/dri/common/ \
-@HAVE_DRICOMMON_TRUE@	-I$(top_srcdir)/src/mesa/drivers/dri/common/ \
-@HAVE_DRICOMMON_TRUE@	-I$(top_srcdir)/src/mesa/ \
-@HAVE_DRICOMMON_TRUE@	-I$(top_srcdir)/src/mapi/ \
-@HAVE_DRICOMMON_TRUE@	-DUSE_DRICONF
-
-@HAVE_DRICOMMON_TRUE@am__append_2 = \
-@HAVE_DRICOMMON_TRUE@	$(top_builddir)/src/mesa/drivers/dri/common/libxmlconfig.la
-
-@HAVE_LIBDRM_TRUE@am__append_3 = \
+@HAVE_LIBDRM_TRUE@am__append_1 = \
 @HAVE_LIBDRM_TRUE@	$(LIBDRM_LIBS)
 
-@HAVE_DRI3_TRUE@am__append_4 = libloader_dri3_helper.la
+@HAVE_DRI3_TRUE@@HAVE_PLATFORM_X11_TRUE@am__append_2 = libloader_dri3_helper.la
 subdir = src/loader
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
-am__aclocal_m4_deps = $(top_srcdir)/m4/ax_check_gnu_make.m4 \
+am__aclocal_m4_deps = $(top_srcdir)/m4/ax_check_compile_flag.m4 \
+	$(top_srcdir)/m4/ax_check_gnu_make.m4 \
 	$(top_srcdir)/m4/ax_check_python_mako_module.m4 \
 	$(top_srcdir)/m4/ax_gcc_builtin.m4 \
 	$(top_srcdir)/m4/ax_gcc_func_attribute.m4 \
@@ -108,7 +99,7 @@ CONFIG_CLEAN_VPATH_FILES =
 LTLIBRARIES = $(noinst_LTLIBRARIES)
 am__DEPENDENCIES_1 =
 @HAVE_LIBDRM_TRUE@am__DEPENDENCIES_2 = $(am__DEPENDENCIES_1)
-libloader_la_DEPENDENCIES = $(am__append_2) $(am__DEPENDENCIES_2)
+libloader_la_DEPENDENCIES = $(am__DEPENDENCIES_2)
 am__objects_1 = libloader_la-loader.lo \
 	libloader_la-pci_id_driver_map.lo
 am_libloader_la_OBJECTS = $(am__objects_1)
@@ -117,15 +108,15 @@ AM_V_lt = $(am__v_lt_@AM_V@)
 am__v_lt_ = $(am__v_lt_@AM_DEFAULT_V@)
 am__v_lt_0 = --silent
 am__v_lt_1 = 
-@HAVE_DRI3_TRUE@libloader_dri3_helper_la_DEPENDENCIES =  \
-@HAVE_DRI3_TRUE@	$(am__DEPENDENCIES_1)
+@HAVE_DRI3_TRUE@@HAVE_PLATFORM_X11_TRUE@libloader_dri3_helper_la_DEPENDENCIES =  \
+@HAVE_DRI3_TRUE@@HAVE_PLATFORM_X11_TRUE@	$(am__DEPENDENCIES_1)
 am__libloader_dri3_helper_la_SOURCES_DIST = loader_dri3_helper.c \
 	loader_dri3_helper.h
-@HAVE_DRI3_TRUE@am_libloader_dri3_helper_la_OBJECTS =  \
-@HAVE_DRI3_TRUE@	loader_dri3_helper.lo
+@HAVE_DRI3_TRUE@@HAVE_PLATFORM_X11_TRUE@am_libloader_dri3_helper_la_OBJECTS =  \
+@HAVE_DRI3_TRUE@@HAVE_PLATFORM_X11_TRUE@	loader_dri3_helper.lo
 libloader_dri3_helper_la_OBJECTS =  \
 	$(am_libloader_dri3_helper_la_OBJECTS)
-@HAVE_DRI3_TRUE@am_libloader_dri3_helper_la_rpath =
+@HAVE_DRI3_TRUE@@HAVE_PLATFORM_X11_TRUE@am_libloader_dri3_helper_la_rpath =
 AM_V_P = $(am__v_P_@AM_V@)
 am__v_P_ = $(am__v_P_@AM_DEFAULT_V@)
 am__v_P_0 = false
@@ -176,6 +167,8 @@ AMDGPU_CFLAGS = @AMDGPU_CFLAGS@
 AMDGPU_LIBS = @AMDGPU_LIBS@
 AMTAR = @AMTAR@
 AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
+ANDROID_CFLAGS = @ANDROID_CFLAGS@
+ANDROID_LIBS = @ANDROID_LIBS@
 AR = @AR@
 AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
@@ -206,8 +199,6 @@ DLLTOOL = @DLLTOOL@
 DLOPEN_LIBS = @DLOPEN_LIBS@
 DRI2PROTO_CFLAGS = @DRI2PROTO_CFLAGS@
 DRI2PROTO_LIBS = @DRI2PROTO_LIBS@
-DRI3PROTO_CFLAGS = @DRI3PROTO_CFLAGS@
-DRI3PROTO_LIBS = @DRI3PROTO_LIBS@
 DRIGL_CFLAGS = @DRIGL_CFLAGS@
 DRIGL_LIBS = @DRIGL_LIBS@
 DRI_DRIVER_INSTALL_DIR = @DRI_DRIVER_INSTALL_DIR@
@@ -220,10 +211,11 @@ ECHO_C = @ECHO_C@
 ECHO_N = @ECHO_N@
 ECHO_T = @ECHO_T@
 EGL_CFLAGS = @EGL_CFLAGS@
-EGL_CLIENT_APIS = @EGL_CLIENT_APIS@
 EGL_LIB_DEPS = @EGL_LIB_DEPS@
 EGL_NATIVE_PLATFORM = @EGL_NATIVE_PLATFORM@
 EGREP = @EGREP@
+ETNAVIV_CFLAGS = @ETNAVIV_CFLAGS@
+ETNAVIV_LIBS = @ETNAVIV_LIBS@
 EXEEXT = @EXEEXT@
 EXPAT_CFLAGS = @EXPAT_CFLAGS@
 EXPAT_LIBS = @EXPAT_LIBS@
@@ -250,6 +242,8 @@ GL_PC_LIB_PRIV = @GL_PC_LIB_PRIV@
 GL_PC_REQ_PRIV = @GL_PC_REQ_PRIV@
 GREP = @GREP@
 HAVE_XF86VIDMODE = @HAVE_XF86VIDMODE@
+I915_CFLAGS = @I915_CFLAGS@
+I915_LIBS = @I915_LIBS@
 INDENT = @INDENT@
 INDENT_FLAGS = @INDENT_FLAGS@
 INSTALL = @INSTALL@
@@ -257,45 +251,40 @@ INSTALL_DATA = @INSTALL_DATA@
 INSTALL_PROGRAM = @INSTALL_PROGRAM@
 INSTALL_SCRIPT = @INSTALL_SCRIPT@
 INSTALL_STRIP_PROGRAM = @INSTALL_STRIP_PROGRAM@
-INTEL_CFLAGS = @INTEL_CFLAGS@
-INTEL_LIBS = @INTEL_LIBS@
 LD = @LD@
 LDFLAGS = @LDFLAGS@
 LD_NO_UNDEFINED = @LD_NO_UNDEFINED@
 LEX = @LEX@
 LEXLIB = @LEXLIB@
 LEX_OUTPUT_ROOT = @LEX_OUTPUT_ROOT@
+LIBATOMIC_LIBS = @LIBATOMIC_LIBS@
 LIBCLC_INCLUDEDIR = @LIBCLC_INCLUDEDIR@
 LIBCLC_LIBEXECDIR = @LIBCLC_LIBEXECDIR@
 LIBDRM_CFLAGS = @LIBDRM_CFLAGS@
 LIBDRM_LIBS = @LIBDRM_LIBS@
 LIBELF_CFLAGS = @LIBELF_CFLAGS@
 LIBELF_LIBS = @LIBELF_LIBS@
+LIBGLVND_DATADIR = @LIBGLVND_DATADIR@
 LIBOBJS = @LIBOBJS@
 LIBS = @LIBS@
-LIBSENSORS_LDFLAGS = @LIBSENSORS_LDFLAGS@
-LIBSHA1_CFLAGS = @LIBSHA1_CFLAGS@
-LIBSHA1_LIBS = @LIBSHA1_LIBS@
+LIBSENSORS_LIBS = @LIBSENSORS_LIBS@
 LIBTOOL = @LIBTOOL@
+LIBUNWIND_CFLAGS = @LIBUNWIND_CFLAGS@
+LIBUNWIND_LIBS = @LIBUNWIND_LIBS@
 LIB_DIR = @LIB_DIR@
 LIB_EXT = @LIB_EXT@
 LIPO = @LIPO@
-LLVM_BINDIR = @LLVM_BINDIR@
 LLVM_CFLAGS = @LLVM_CFLAGS@
 LLVM_CONFIG = @LLVM_CONFIG@
-LLVM_CPPFLAGS = @LLVM_CPPFLAGS@
 LLVM_CXXFLAGS = @LLVM_CXXFLAGS@
 LLVM_INCLUDEDIR = @LLVM_INCLUDEDIR@
 LLVM_LDFLAGS = @LLVM_LDFLAGS@
-LLVM_LIBDIR = @LLVM_LIBDIR@
 LLVM_LIBS = @LLVM_LIBS@
-LLVM_VERSION = @LLVM_VERSION@
 LN_S = @LN_S@
 LTLIBOBJS = @LTLIBOBJS@
 MAINT = @MAINT@
 MAKEINFO = @MAKEINFO@
 MANIFEST_TOOL = @MANIFEST_TOOL@
-MESA_LLVM = @MESA_LLVM@
 MKDIR_P = @MKDIR_P@
 MSVC2013_COMPAT_CFLAGS = @MSVC2013_COMPAT_CFLAGS@
 MSVC2013_COMPAT_CXXFLAGS = @MSVC2013_COMPAT_CXXFLAGS@
@@ -311,13 +300,11 @@ NVVIEUX_CFLAGS = @NVVIEUX_CFLAGS@
 NVVIEUX_LIBS = @NVVIEUX_LIBS@
 OBJDUMP = @OBJDUMP@
 OBJEXT = @OBJEXT@
-OMX_CFLAGS = @OMX_CFLAGS@
-OMX_LIBS = @OMX_LIBS@
-OMX_LIB_INSTALL_DIR = @OMX_LIB_INSTALL_DIR@
+OMX_BELLAGIO_CFLAGS = @OMX_BELLAGIO_CFLAGS@
+OMX_BELLAGIO_LIBS = @OMX_BELLAGIO_LIBS@
+OMX_BELLAGIO_LIB_INSTALL_DIR = @OMX_BELLAGIO_LIB_INSTALL_DIR@
 OPENCL_LIBNAME = @OPENCL_LIBNAME@
 OPENCL_VERSION = @OPENCL_VERSION@
-OPENSSL_CFLAGS = @OPENSSL_CFLAGS@
-OPENSSL_LIBS = @OPENSSL_LIBS@
 OSMESA_LIB = @OSMESA_LIB@
 OSMESA_LIB_DEPS = @OSMESA_LIB_DEPS@
 OSMESA_PC_LIB_PRIV = @OSMESA_PC_LIB_PRIV@
@@ -337,8 +324,6 @@ PKG_CONFIG = @PKG_CONFIG@
 PKG_CONFIG_LIBDIR = @PKG_CONFIG_LIBDIR@
 PKG_CONFIG_PATH = @PKG_CONFIG_PATH@
 POSIX_SHELL = @POSIX_SHELL@
-PRESENTPROTO_CFLAGS = @PRESENTPROTO_CFLAGS@
-PRESENTPROTO_LIBS = @PRESENTPROTO_LIBS@
 PTHREADSTUBS_CFLAGS = @PTHREADSTUBS_CFLAGS@
 PTHREADSTUBS_LIBS = @PTHREADSTUBS_LIBS@
 PTHREAD_CC = @PTHREAD_CC@
@@ -354,8 +339,6 @@ SED = @SED@
 SELINUX_CFLAGS = @SELINUX_CFLAGS@
 SELINUX_LIBS = @SELINUX_LIBS@
 SET_MAKE = @SET_MAKE@
-SHA1_CFLAGS = @SHA1_CFLAGS@
-SHA1_LIBS = @SHA1_LIBS@
 SHELL = @SHELL@
 SIMPENROSE_CFLAGS = @SIMPENROSE_CFLAGS@
 SIMPENROSE_LIBS = @SIMPENROSE_LIBS@
@@ -364,7 +347,8 @@ STRIP = @STRIP@
 SWR_AVX2_CXXFLAGS = @SWR_AVX2_CXXFLAGS@
 SWR_AVX_CXXFLAGS = @SWR_AVX_CXXFLAGS@
 SWR_CXX11_CXXFLAGS = @SWR_CXX11_CXXFLAGS@
-TIMESTAMP_CMD = @TIMESTAMP_CMD@
+SWR_KNL_CXXFLAGS = @SWR_KNL_CXXFLAGS@
+SWR_SKX_CXXFLAGS = @SWR_SKX_CXXFLAGS@
 VALGRIND_CFLAGS = @VALGRIND_CFLAGS@
 VALGRIND_LIBS = @VALGRIND_LIBS@
 VA_CFLAGS = @VA_CFLAGS@
@@ -372,25 +356,28 @@ VA_LIBS = @VA_LIBS@
 VA_LIB_INSTALL_DIR = @VA_LIB_INSTALL_DIR@
 VA_MAJOR = @VA_MAJOR@
 VA_MINOR = @VA_MINOR@
-VC4_CFLAGS = @VC4_CFLAGS@
-VC4_LIBS = @VC4_LIBS@
+VC5_SIMULATOR_CFLAGS = @VC5_SIMULATOR_CFLAGS@
+VC5_SIMULATOR_LIBS = @VC5_SIMULATOR_LIBS@
 VDPAU_CFLAGS = @VDPAU_CFLAGS@
 VDPAU_LIBS = @VDPAU_LIBS@
 VDPAU_LIB_INSTALL_DIR = @VDPAU_LIB_INSTALL_DIR@
 VDPAU_MAJOR = @VDPAU_MAJOR@
 VDPAU_MINOR = @VDPAU_MINOR@
 VERSION = @VERSION@
-VG_LIB_DEPS = @VG_LIB_DEPS@
 VISIBILITY_CFLAGS = @VISIBILITY_CFLAGS@
 VISIBILITY_CXXFLAGS = @VISIBILITY_CXXFLAGS@
 VL_CFLAGS = @VL_CFLAGS@
 VL_LIBS = @VL_LIBS@
 VULKAN_ICD_INSTALL_DIR = @VULKAN_ICD_INSTALL_DIR@
-WAYLAND_CFLAGS = @WAYLAND_CFLAGS@
-WAYLAND_LIBS = @WAYLAND_LIBS@
+WAYLAND_CLIENT_CFLAGS = @WAYLAND_CLIENT_CFLAGS@
+WAYLAND_CLIENT_LIBS = @WAYLAND_CLIENT_LIBS@
+WAYLAND_PROTOCOLS_DATADIR = @WAYLAND_PROTOCOLS_DATADIR@
 WAYLAND_SCANNER = @WAYLAND_SCANNER@
 WAYLAND_SCANNER_CFLAGS = @WAYLAND_SCANNER_CFLAGS@
 WAYLAND_SCANNER_LIBS = @WAYLAND_SCANNER_LIBS@
+WAYLAND_SERVER_CFLAGS = @WAYLAND_SERVER_CFLAGS@
+WAYLAND_SERVER_LIBS = @WAYLAND_SERVER_LIBS@
+WNO_OVERRIDE_INIT = @WNO_OVERRIDE_INIT@
 X11_INCLUDES = @X11_INCLUDES@
 XA_MAJOR = @XA_MAJOR@
 XA_MINOR = @XA_MINOR@
@@ -409,9 +396,10 @@ XVMC_LIBS = @XVMC_LIBS@
 XVMC_LIB_INSTALL_DIR = @XVMC_LIB_INSTALL_DIR@
 XVMC_MAJOR = @XVMC_MAJOR@
 XVMC_MINOR = @XVMC_MINOR@
-XXD = @XXD@
 YACC = @YACC@
 YFLAGS = @YFLAGS@
+ZLIB_CFLAGS = @ZLIB_CFLAGS@
+ZLIB_LIBS = @ZLIB_LIBS@
 abs_builddir = @abs_builddir@
 abs_srcdir = @abs_srcdir@
 abs_top_builddir = @abs_top_builddir@
@@ -479,8 +467,10 @@ LOADER_C_FILES := \
 	pci_id_driver_map.h
 
 EXTRA_DIST = SConscript
-noinst_LTLIBRARIES = libloader.la $(am__append_4)
+noinst_LTLIBRARIES = libloader.la $(am__append_2)
 AM_CPPFLAGS = \
+	-I$(top_builddir)/src/util/ \
+	-DUSE_DRICONF \
 	$(DEFINES) \
 	-I$(top_srcdir)/include \
 	-I$(top_srcdir)/src \
@@ -488,14 +478,14 @@ AM_CPPFLAGS = \
 	$(XCB_DRI3_CFLAGS) \
 	$(LIBDRM_CFLAGS)
 
-libloader_la_CPPFLAGS = $(AM_CPPFLAGS) $(am__append_1)
+libloader_la_CPPFLAGS = $(AM_CPPFLAGS)
 libloader_la_SOURCES = $(LOADER_C_FILES)
-libloader_la_LIBADD = $(am__append_2) $(am__append_3)
-@HAVE_DRI3_TRUE@libloader_dri3_helper_la_SOURCES = \
-@HAVE_DRI3_TRUE@	loader_dri3_helper.c \
-@HAVE_DRI3_TRUE@	loader_dri3_helper.h
+libloader_la_LIBADD = $(am__append_1)
+@HAVE_DRI3_TRUE@@HAVE_PLATFORM_X11_TRUE@libloader_dri3_helper_la_SOURCES = \
+@HAVE_DRI3_TRUE@@HAVE_PLATFORM_X11_TRUE@	loader_dri3_helper.c \
+@HAVE_DRI3_TRUE@@HAVE_PLATFORM_X11_TRUE@	loader_dri3_helper.h
 
-@HAVE_DRI3_TRUE@libloader_dri3_helper_la_LIBADD = $(XCB_DRI3_LIBS)
+@HAVE_DRI3_TRUE@@HAVE_PLATFORM_X11_TRUE@libloader_dri3_helper_la_LIBADD = $(XCB_DRI3_LIBS)
 all: all-am
 
 .SUFFIXES:
diff --git a/lib/mesa/src/loader/loader.c b/lib/mesa/src/loader/loader.c
index fe9030776..182ba90a0 100644
--- a/lib/mesa/src/loader/loader.c
+++ b/lib/mesa/src/loader/loader.c
@@ -33,6 +33,8 @@
 #include <stdio.h>
 #include <stdbool.h>
 #include <string.h>
+#include <unistd.h>
+#include <stdlib.h>
 #ifdef MAJOR_IN_MKDEV
 #include <sys/mkdev.h>
 #endif
@@ -42,12 +44,10 @@
 #include "loader.h"
 
 #ifdef HAVE_LIBDRM
-#include <stdlib.h>
-#include <unistd.h>
 #include <xf86drm.h>
 #ifdef USE_DRICONF
-#include "xmlconfig.h"
-#include "xmlpool.h"
+#include "util/xmlconfig.h"
+#include "util/xmlpool.h"
 #endif
 #endif
 
@@ -145,7 +145,7 @@ static char *drm_get_id_path_tag_for_fd(int fd)
    drmDevicePtr device;
    char *tag;
 
-   if (drmGetDevice(fd, &device) != 0)
+   if (drmGetDevice2(fd, 0, &device) != 0)
        return NULL;
 
    tag = drm_construct_id_path_tag(device);
@@ -153,7 +153,7 @@ static char *drm_get_id_path_tag_for_fd(int fd)
    return tag;
 }
 
-int loader_get_user_preferred_fd(int default_fd, int *different_device)
+int loader_get_user_preferred_fd(int default_fd, bool *different_device)
 {
 /* Arbitrary "maximum" value of drm devices. */
 #define MAX_DRM_DEVICES 32
@@ -171,7 +171,7 @@ int loader_get_user_preferred_fd(int default_fd, int *different_device)
 #endif
 
    if (prime == NULL) {
-      *different_device = 0;
+      *different_device = false;
       return default_fd;
    }
 
@@ -179,7 +179,7 @@ int loader_get_user_preferred_fd(int default_fd, int *different_device)
    if (default_tag == NULL)
       goto err;
 
-   num_devices = drmGetDevices(devices, MAX_DRM_DEVICES);
+   num_devices = drmGetDevices2(0, devices, MAX_DRM_DEVICES);
    if (num_devices < 0)
       goto err;
 
@@ -230,16 +230,16 @@ int loader_get_user_preferred_fd(int default_fd, int *different_device)
    return fd;
 
  err:
-   *different_device = 0;
+   *different_device = false;
 
    free(default_tag);
    free(prime);
    return default_fd;
 }
 #else
-int loader_get_user_preferred_fd(int default_fd, int *different_device)
+int loader_get_user_preferred_fd(int default_fd, bool *different_device)
 {
-   *different_device = 0;
+   *different_device = false;
    return default_fd;
 }
 #endif
@@ -275,14 +275,14 @@ drm_get_pci_id_for_fd(int fd, int *vendor_id, int *chip_id)
    drmDevicePtr device;
    int ret;
 
-   if (drmGetDevice(fd, &device) == 0) {
+   if (drmGetDevice2(fd, 0, &device) == 0) {
       if (device->bustype == DRM_BUS_PCI) {
          *vendor_id = device->deviceinfo.pci->vendor_id;
          *chip_id = device->deviceinfo.pci->device_id;
          ret = 1;
       }
       else {
-         log_(_LOADER_WARNING, "MESA-LOADER: device is not located on the PCI bus\n");
+         log_(_LOADER_DEBUG, "MESA-LOADER: device is not located on the PCI bus\n");
          ret = 0;
       }
       drmFreeDevice(&device);
@@ -345,6 +345,17 @@ loader_get_driver_for_fd(int fd)
    int vendor_id, chip_id, i, j;
    char *driver = NULL;
 
+   /* Allow an environment variable to force choosing a different driver
+    * binary.  If that driver binary can't survive on this FD, that's the
+    * user's problem, but this allows vc4 simulator to run on an i965 host,
+    * and may be useful for some touch testing of i915 on an i965 host.
+    */
+   if (geteuid() == getuid()) {
+      driver = getenv("MESA_LOADER_DRIVER_OVERRIDE");
+      if (driver)
+         return strdup(driver);
+   }
+
    if (!loader_get_pci_id_for_fd(fd, &vendor_id, &chip_id)) {
 
 #if HAVE_LIBDRM
@@ -396,3 +407,28 @@ loader_set_logger(void (*logger)(int level, const char *fmt, ...))
 {
    log_ = logger;
 }
+
+/* XXX: Local definition to avoid pulling the heavyweight GL/gl.h and
+ * GL/internal/dri_interface.h
+ */
+
+#ifndef __DRI_DRIVER_GET_EXTENSIONS
+#define __DRI_DRIVER_GET_EXTENSIONS "__driDriverGetExtensions"
+#endif
+
+char *
+loader_get_extensions_name(const char *driver_name)
+{
+   char *name = NULL;
+
+   if (asprintf(&name, "%s_%s", __DRI_DRIVER_GET_EXTENSIONS, driver_name) < 0)
+      return NULL;
+
+   const size_t len = strlen(name);
+   for (size_t i = 0; i < len; i++) {
+	   if (name[i] == '-')
+		   name[i] = '_';
+   }
+
+   return name;
+}
diff --git a/lib/mesa/src/loader/loader.h b/lib/mesa/src/loader/loader.h
index d404f5b67..3859b45dc 100644
--- a/lib/mesa/src/loader/loader.h
+++ b/lib/mesa/src/loader/loader.h
@@ -27,6 +27,8 @@
 #ifndef LOADER_H
 #define LOADER_H
 
+#include <stdbool.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -51,7 +53,7 @@ loader_get_device_name_for_fd(int fd);
  */
 
 int
-loader_get_user_preferred_fd(int default_fd, int *different_device);
+loader_get_user_preferred_fd(int default_fd, bool *different_device);
 
 /* for logging.. keep this aligned with egllog.h so we can just use
  * _eglLog directly.
@@ -65,6 +67,8 @@ loader_get_user_preferred_fd(int default_fd, int *different_device);
 void
 loader_set_logger(void (*logger)(int level, const char *fmt, ...));
 
+char *
+loader_get_extensions_name(const char *driver_name);
 
 #ifdef __cplusplus
 }
diff --git a/lib/mesa/src/loader/loader_dri3_helper.c b/lib/mesa/src/loader/loader_dri3_helper.c
index d465a41e2..b4c458201 100644
--- a/lib/mesa/src/loader/loader_dri3_helper.c
+++ b/lib/mesa/src/loader/loader_dri3_helper.c
@@ -40,6 +40,127 @@
 #define DRI_CONF_VBLANK_DEF_INTERVAL_1 2
 #define DRI_CONF_VBLANK_ALWAYS_SYNC 3
 
+/**
+ * A cached blit context.
+ */
+struct loader_dri3_blit_context {
+   mtx_t mtx;
+   __DRIcontext *ctx;
+   __DRIscreen *cur_screen;
+   const __DRIcoreExtension *core;
+};
+
+/* For simplicity we maintain the cache only for a single screen at a time */
+static struct loader_dri3_blit_context blit_context = {
+   _MTX_INITIALIZER_NP, NULL
+};
+
+static void
+dri3_flush_present_events(struct loader_dri3_drawable *draw);
+
+static struct loader_dri3_buffer *
+dri3_find_back_alloc(struct loader_dri3_drawable *draw);
+
+/**
+ * Do we have blit functionality in the image blit extension?
+ *
+ * \param draw[in]  The drawable intended to blit from / to.
+ * \return  true if we have blit functionality. false otherwise.
+ */
+static bool loader_dri3_have_image_blit(const struct loader_dri3_drawable *draw)
+{
+   return draw->ext->image->base.version >= 9 &&
+      draw->ext->image->blitImage != NULL;
+}
+
+/**
+ * Get and lock (for use with the current thread) a dri context associated
+ * with the drawable's dri screen. The context is intended to be used with
+ * the dri image extension's blitImage method.
+ *
+ * \param draw[in]  Pointer to the drawable whose dri screen we want a
+ * dri context for.
+ * \return A dri context or NULL if context creation failed.
+ *
+ * When the caller is done with the context (even if the context returned was
+ * NULL), the caller must call loader_dri3_blit_context_put.
+ */
+static __DRIcontext *
+loader_dri3_blit_context_get(struct loader_dri3_drawable *draw)
+{
+   mtx_lock(&blit_context.mtx);
+
+   if (blit_context.ctx && blit_context.cur_screen != draw->dri_screen) {
+      blit_context.core->destroyContext(blit_context.ctx);
+      blit_context.ctx = NULL;
+   }
+
+   if (!blit_context.ctx) {
+      blit_context.ctx = draw->ext->core->createNewContext(draw->dri_screen,
+                                                           NULL, NULL, NULL);
+      blit_context.cur_screen = draw->dri_screen;
+      blit_context.core = draw->ext->core;
+   }
+
+   return blit_context.ctx;
+}
+
+/**
+ * Release (for use with other threads) a dri context previously obtained using
+ * loader_dri3_blit_context_get.
+ */
+static void
+loader_dri3_blit_context_put(void)
+{
+   mtx_unlock(&blit_context.mtx);
+}
+
+/**
+ * Blit (parts of) the contents of a DRI image to another dri image
+ *
+ * \param draw[in]  The drawable which owns the images.
+ * \param dst[in]  The destination image.
+ * \param src[in]  The source image.
+ * \param dstx0[in]  Start destination coordinate.
+ * \param dsty0[in]  Start destination coordinate.
+ * \param width[in]  Blit width.
+ * \param height[in] Blit height.
+ * \param srcx0[in]  Start source coordinate.
+ * \param srcy0[in]  Start source coordinate.
+ * \param flush_flag[in]  Image blit flush flag.
+ * \return true iff successful.
+ */
+static bool
+loader_dri3_blit_image(struct loader_dri3_drawable *draw,
+                       __DRIimage *dst, __DRIimage *src,
+                       int dstx0, int dsty0, int width, int height,
+                       int srcx0, int srcy0, int flush_flag)
+{
+   __DRIcontext *dri_context;
+   bool use_blit_context = false;
+
+   if (!loader_dri3_have_image_blit(draw))
+      return false;
+
+   dri_context = draw->vtable->get_dri_context(draw);
+
+   if (!dri_context || !draw->vtable->in_current_context(draw)) {
+      dri_context = loader_dri3_blit_context_get(draw);
+      use_blit_context = true;
+      flush_flag |= __BLIT_FLAG_FLUSH;
+   }
+
+   if (dri_context)
+      draw->ext->image->blitImage(dri_context, dst, src, dstx0, dsty0,
+                                  width, height, srcx0, srcy0,
+                                  width, height, flush_flag);
+
+   if (use_blit_context)
+      loader_dri3_blit_context_put();
+
+   return dri_context != NULL;
+}
+
 static inline void
 dri3_fence_reset(xcb_connection_t *c, struct loader_dri3_buffer *buffer)
 {
@@ -59,10 +180,16 @@ dri3_fence_trigger(xcb_connection_t *c, struct loader_dri3_buffer *buffer)
 }
 
 static inline void
-dri3_fence_await(xcb_connection_t *c, struct loader_dri3_buffer *buffer)
+dri3_fence_await(xcb_connection_t *c, struct loader_dri3_drawable *draw,
+                 struct loader_dri3_buffer *buffer)
 {
    xcb_flush(c);
    xshmfence_await(buffer->shm_fence);
+   if (draw) {
+      mtx_lock(&draw->mtx);
+      dri3_flush_present_events(draw);
+      mtx_unlock(&draw->mtx);
+   }
 }
 
 static void
@@ -77,9 +204,7 @@ dri3_update_num_back(struct loader_dri3_drawable *draw)
 void
 loader_dri3_set_swap_interval(struct loader_dri3_drawable *draw, int interval)
 {
-   interval = draw->vtable->clamp_swap_interval(draw, interval);
-   draw->vtable->set_swap_interval(draw, interval);
-   dri3_update_num_back(draw);
+   draw->swap_interval = interval;
 }
 
 /** dri3_free_render_buffer
@@ -95,9 +220,9 @@ dri3_free_render_buffer(struct loader_dri3_drawable *draw,
       xcb_free_pixmap(draw->conn, buffer->pixmap);
    xcb_sync_destroy_fence(draw->conn, buffer->sync_fence);
    xshmfence_unmap_shm(buffer->shm_fence);
-   (draw->ext->image->destroyImage)(buffer->image);
+   draw->ext->image->destroyImage(buffer->image);
    if (buffer->linear_buffer)
-      (draw->ext->image->destroyImage)(buffer->linear_buffer);
+      draw->ext->image->destroyImage(buffer->linear_buffer);
    free(buffer);
 }
 
@@ -106,7 +231,7 @@ loader_dri3_drawable_fini(struct loader_dri3_drawable *draw)
 {
    int i;
 
-   (draw->ext->core->destroyDrawable)(draw->dri_drawable);
+   draw->ext->core->destroyDrawable(draw->dri_drawable);
 
    for (i = 0; i < LOADER_DRI3_NUM_BUFFERS; i++) {
       if (draw->buffers[i])
@@ -121,6 +246,9 @@ loader_dri3_drawable_fini(struct loader_dri3_drawable *draw)
       xcb_discard_reply(draw->conn, cookie.sequence);
       xcb_unregister_for_special_event(draw->conn, draw->special_event);
    }
+
+   cnd_destroy(&draw->event_cnd);
+   mtx_destroy(&draw->mtx);
 }
 
 int
@@ -150,6 +278,11 @@ loader_dri3_drawable_init(xcb_connection_t *conn,
    draw->have_fake_front = 0;
    draw->first_init = true;
 
+   draw->cur_blit_source = -1;
+   draw->back_format = __DRI_IMAGE_FORMAT_NONE;
+   mtx_init(&draw->mtx, mtx_plain);
+   cnd_init(&draw->event_cnd);
+
    if (draw->ext->config)
       draw->ext->config->configQueryi(draw->dri_screen,
                                       "vblank_mode", &vblank_mode);
@@ -165,15 +298,15 @@ loader_dri3_drawable_init(xcb_connection_t *conn,
       swap_interval = 1;
       break;
    }
-   draw->vtable->set_swap_interval(draw, swap_interval);
+   draw->swap_interval = swap_interval;
 
    dri3_update_num_back(draw);
 
    /* Create a new drawable */
    draw->dri_drawable =
-      (draw->ext->image_driver->createNewDrawable)(dri_screen,
-                                                   dri_config,
-                                                   draw);
+      draw->ext->image_driver->createNewDrawable(dri_screen,
+                                                 dri_config,
+                                                 draw);
 
    if (!draw->dri_drawable)
       return 1;
@@ -191,6 +324,13 @@ loader_dri3_drawable_init(xcb_connection_t *conn,
    draw->vtable->set_drawable_size(draw, draw->width, draw->height);
    free(reply);
 
+   draw->swap_method = __DRI_ATTRIB_SWAP_UNDEFINED;
+   if (draw->ext->core->base.version >= 2) {
+      (void )draw->ext->core->getConfigAttrib(dri_config,
+                                              __DRI_ATTRIB_SWAP_METHOD,
+                                              &draw->swap_method);
+   }
+
    /*
     * Make sure server has the same swap interval we do for the new
     * drawable.
@@ -214,6 +354,7 @@ dri3_handle_present_event(struct loader_dri3_drawable *draw,
       draw->width = ce->width;
       draw->height = ce->height;
       draw->vtable->set_drawable_size(draw, draw->width, draw->height);
+      draw->ext->flush->invalidate(draw->dri_drawable);
       break;
    }
    case XCB_PRESENT_COMPLETE_NOTIFY: {
@@ -235,7 +376,6 @@ dri3_handle_present_event(struct loader_dri3_drawable *draw,
             draw->flipping = false;
             break;
          }
-         dri3_update_num_back(draw);
 
          if (draw->vtable->show_fps)
             draw->vtable->show_fps(draw, ce->ust);
@@ -256,13 +396,14 @@ dri3_handle_present_event(struct loader_dri3_drawable *draw,
       for (b = 0; b < sizeof(draw->buffers) / sizeof(draw->buffers[0]); b++) {
          struct loader_dri3_buffer *buf = draw->buffers[b];
 
-         if (buf && buf->pixmap == ie->pixmap) {
+         if (buf && buf->pixmap == ie->pixmap)
             buf->busy = 0;
-            if (draw->num_back <= b && b < LOADER_DRI3_MAX_BACK) {
-               dri3_free_render_buffer(draw, buf);
-               draw->buffers[b] = NULL;
-            }
-            break;
+
+         if (buf && draw->num_back <= b && b < LOADER_DRI3_MAX_BACK &&
+             draw->cur_blit_source != b &&
+             !buf->busy) {
+            dri3_free_render_buffer(draw, buf);
+            draw->buffers[b] = NULL;
          }
       }
       break;
@@ -272,13 +413,27 @@ dri3_handle_present_event(struct loader_dri3_drawable *draw,
 }
 
 static bool
-dri3_wait_for_event(struct loader_dri3_drawable *draw)
+dri3_wait_for_event_locked(struct loader_dri3_drawable *draw)
 {
    xcb_generic_event_t *ev;
    xcb_present_generic_event_t *ge;
 
    xcb_flush(draw->conn);
-   ev = xcb_wait_for_special_event(draw->conn, draw->special_event);
+
+   /* Only have one thread waiting for events at a time */
+   if (draw->has_event_waiter) {
+      cnd_wait(&draw->event_cnd, &draw->mtx);
+      /* Another thread has updated the protected info, so retest. */
+      return true;
+   } else {
+      draw->has_event_waiter = true;
+      /* Allow other threads access to the drawable while we're waiting. */
+      mtx_unlock(&draw->mtx);
+      ev = xcb_wait_for_special_event(draw->conn, draw->special_event);
+      mtx_lock(&draw->mtx);
+      draw->has_event_waiter = false;
+      cnd_broadcast(&draw->event_cnd);
+   }
    if (!ev)
       return false;
    ge = (void *) ev;
@@ -307,19 +462,23 @@ loader_dri3_wait_for_msc(struct loader_dri3_drawable *draw,
                           divisor,
                           remainder);
 
+   mtx_lock(&draw->mtx);
    xcb_flush(draw->conn);
 
    /* Wait for the event */
    if (draw->special_event) {
       while ((int32_t) (msc_serial - draw->recv_msc_serial) > 0) {
-         if (!dri3_wait_for_event(draw))
+         if (!dri3_wait_for_event_locked(draw)) {
+            mtx_unlock(&draw->mtx);
             return false;
+         }
       }
    }
 
    *ust = draw->notify_ust;
    *msc = draw->notify_msc;
    *sbc = draw->recv_sbc;
+   mtx_unlock(&draw->mtx);
 
    return true;
 }
@@ -341,17 +500,21 @@ loader_dri3_wait_for_sbc(struct loader_dri3_drawable *draw,
     *      swaps requested with glXSwapBuffersMscOML for that window have
     *      completed."
     */
+   mtx_lock(&draw->mtx);
    if (!target_sbc)
       target_sbc = draw->send_sbc;
 
    while (draw->recv_sbc < target_sbc) {
-      if (!dri3_wait_for_event(draw))
+      if (!dri3_wait_for_event_locked(draw)) {
+         mtx_unlock(&draw->mtx);
          return 0;
+      }
    }
 
    *ust = draw->ust;
    *msc = draw->msc;
    *sbc = draw->recv_sbc;
+   mtx_unlock(&draw->mtx);
    return 1;
 }
 
@@ -364,25 +527,37 @@ static int
 dri3_find_back(struct loader_dri3_drawable *draw)
 {
    int b;
-   xcb_generic_event_t *ev;
-   xcb_present_generic_event_t *ge;
+   int num_to_consider;
+
+   mtx_lock(&draw->mtx);
+   /* Increase the likelyhood of reusing current buffer */
+   dri3_flush_present_events(draw);
+
+   /* Check whether we need to reuse the current back buffer as new back.
+    * In that case, wait until it's not busy anymore.
+    */
+   dri3_update_num_back(draw);
+   num_to_consider = draw->num_back;
+   if (!loader_dri3_have_image_blit(draw) && draw->cur_blit_source != -1) {
+      num_to_consider = 1;
+      draw->cur_blit_source = -1;
+   }
 
    for (;;) {
-      for (b = 0; b < draw->num_back; b++) {
+      for (b = 0; b < num_to_consider; b++) {
          int id = LOADER_DRI3_BACK_ID((b + draw->cur_back) % draw->num_back);
          struct loader_dri3_buffer *buffer = draw->buffers[id];
 
          if (!buffer || !buffer->busy) {
             draw->cur_back = id;
+            mtx_unlock(&draw->mtx);
             return id;
          }
       }
-      xcb_flush(draw->conn);
-      ev = xcb_wait_for_special_event(draw->conn, draw->special_event);
-      if (!ev)
+      if (!dri3_wait_for_event_locked(draw)) {
+         mtx_unlock(&draw->mtx);
          return -1;
-      ge = (void *) ev;
-      dri3_handle_present_event(draw, ge);
+      }
    }
 }
 
@@ -468,9 +643,6 @@ loader_dri3_copy_sub_buffer(struct loader_dri3_drawable *draw,
 {
    struct loader_dri3_buffer *back;
    unsigned flags = __DRI2_FLUSH_DRAWABLE;
-   __DRIcontext *dri_context;
-
-   dri_context = draw->vtable->get_dri_context(draw);
 
    /* Check we have the right attachments */
    if (!draw->have_back || draw->is_pixmap)
@@ -480,33 +652,27 @@ loader_dri3_copy_sub_buffer(struct loader_dri3_drawable *draw,
       flags |= __DRI2_FLUSH_CONTEXT;
    loader_dri3_flush(draw, flags, __DRI2_THROTTLE_SWAPBUFFER);
 
-   back = dri3_back_buffer(draw);
+   back = dri3_find_back_alloc(draw);
+   if (!back)
+      return;
+
    y = draw->height - y - height;
 
-   if (draw->is_different_gpu && draw->vtable->in_current_context(draw)) {
+   if (draw->is_different_gpu) {
       /* Update the linear buffer part of the back buffer
        * for the dri3_copy_area operation
        */
-      draw->ext->image->blitImage(dri_context,
-                                  back->linear_buffer,
-                                  back->image,
-                                  0, 0, back->width,
-                                  back->height,
-                                  0, 0, back->width,
-                                  back->height, __BLIT_FLAG_FLUSH);
-      /* We use blitImage to update our fake front,
-       */
-      if (draw->have_fake_front)
-         draw->ext->image->blitImage(dri_context,
-                                     dri3_fake_front_buffer(draw)->image,
-                                     back->image,
-                                     x, y, width, height,
-                                     x, y, width, height, __BLIT_FLAG_FLUSH);
+      (void) loader_dri3_blit_image(draw,
+                                    back->linear_buffer,
+                                    back->image,
+                                    0, 0, back->width, back->height,
+                                    0, 0, __BLIT_FLAG_FLUSH);
    }
 
+   loader_dri3_swapbuffer_barrier(draw);
    dri3_fence_reset(draw->conn, back);
    dri3_copy_area(draw->conn,
-                  dri3_back_buffer(draw)->pixmap,
+                  back->pixmap,
                   draw->drawable,
                   dri3_drawable_gc(draw),
                   x, y, x, y, width, height);
@@ -514,17 +680,23 @@ loader_dri3_copy_sub_buffer(struct loader_dri3_drawable *draw,
    /* Refresh the fake front (if present) after we just damaged the real
     * front.
     */
-   if (draw->have_fake_front && !draw->is_different_gpu) {
+   if (draw->have_fake_front &&
+       !loader_dri3_blit_image(draw,
+                               dri3_fake_front_buffer(draw)->image,
+                               back->image,
+                               x, y, width, height,
+                               x, y, __BLIT_FLAG_FLUSH) &&
+       !draw->is_different_gpu) {
       dri3_fence_reset(draw->conn, dri3_fake_front_buffer(draw));
       dri3_copy_area(draw->conn,
-                     dri3_back_buffer(draw)->pixmap,
+                     back->pixmap,
                      dri3_fake_front_buffer(draw)->pixmap,
                      dri3_drawable_gc(draw),
                      x, y, x, y, width, height);
       dri3_fence_trigger(draw->conn, dri3_fake_front_buffer(draw));
-      dri3_fence_await(draw->conn, dri3_fake_front_buffer(draw));
+      dri3_fence_await(draw->conn, NULL, dri3_fake_front_buffer(draw));
    }
-   dri3_fence_await(draw->conn, back);
+   dri3_fence_await(draw->conn, draw, back);
 }
 
 void
@@ -540,20 +712,18 @@ loader_dri3_copy_drawable(struct loader_dri3_drawable *draw,
                   dri3_drawable_gc(draw),
                   0, 0, 0, 0, draw->width, draw->height);
    dri3_fence_trigger(draw->conn, dri3_fake_front_buffer(draw));
-   dri3_fence_await(draw->conn, dri3_fake_front_buffer(draw));
+   dri3_fence_await(draw->conn, draw, dri3_fake_front_buffer(draw));
 }
 
 void
 loader_dri3_wait_x(struct loader_dri3_drawable *draw)
 {
    struct loader_dri3_buffer *front;
-   __DRIcontext *dri_context;
 
    if (draw == NULL || !draw->have_fake_front)
       return;
 
    front = dri3_fake_front_buffer(draw);
-   dri_context = draw->vtable->get_dri_context(draw);
 
    loader_dri3_copy_drawable(draw, front->pixmap, draw->drawable);
 
@@ -562,39 +732,34 @@ loader_dri3_wait_x(struct loader_dri3_drawable *draw)
     * Copy back to the tiled buffer we use for rendering.
     * Note that we don't need flushing.
     */
-   if (draw->is_different_gpu && draw->vtable->in_current_context(draw))
-      draw->ext->image->blitImage(dri_context,
-                                  front->image,
-                                  front->linear_buffer,
-                                  0, 0, front->width,
-                                  front->height,
-                                  0, 0, front->width,
-                                  front->height, 0);
+   if (draw->is_different_gpu)
+      (void) loader_dri3_blit_image(draw,
+                                    front->image,
+                                    front->linear_buffer,
+                                    0, 0, front->width, front->height,
+                                    0, 0, 0);
 }
 
 void
 loader_dri3_wait_gl(struct loader_dri3_drawable *draw)
 {
    struct loader_dri3_buffer *front;
-   __DRIcontext *dri_context;
 
    if (draw == NULL || !draw->have_fake_front)
       return;
 
    front = dri3_fake_front_buffer(draw);
-   dri_context = draw->vtable->get_dri_context(draw);
 
    /* In the psc->is_different_gpu case, we update the linear_buffer
     * before updating the real front.
     */
-   if (draw->is_different_gpu && draw->vtable->in_current_context(draw))
-      draw->ext->image->blitImage(dri_context,
-                                  front->linear_buffer,
-                                  front->image,
-                                  0, 0, front->width,
-                                  front->height,
-                                  0, 0, front->width,
-                                  front->height, __BLIT_FLAG_FLUSH);
+   if (draw->is_different_gpu)
+      (void) loader_dri3_blit_image(draw,
+                                    front->linear_buffer,
+                                    front->image,
+                                    0, 0, front->width, front->height,
+                                    0, 0, __BLIT_FLAG_FLUSH);
+   loader_dri3_swapbuffer_barrier(draw);
    loader_dri3_copy_drawable(draw, draw->drawable, front->pixmap);
 }
 
@@ -608,6 +773,9 @@ dri3_flush_present_events(struct loader_dri3_drawable *draw)
    /* Check to see if any configuration changes have occurred
     * since we were last invoked
     */
+   if (draw->has_event_waiter)
+      return;
+
    if (draw->special_event) {
       xcb_generic_event_t    *ev;
 
@@ -630,34 +798,42 @@ loader_dri3_swap_buffers_msc(struct loader_dri3_drawable *draw,
                              bool force_copy)
 {
    struct loader_dri3_buffer *back;
-   __DRIcontext *dri_context;
    int64_t ret = 0;
    uint32_t options = XCB_PRESENT_OPTION_NONE;
-   int swap_interval;
-
-   dri_context = draw->vtable->get_dri_context(draw);
-   swap_interval = draw->vtable->get_swap_interval(draw);
 
    draw->vtable->flush_drawable(draw, flush_flags);
 
-   back = draw->buffers[LOADER_DRI3_BACK_ID(draw->cur_back)];
+   back = dri3_find_back_alloc(draw);
+
+   mtx_lock(&draw->mtx);
    if (draw->is_different_gpu && back) {
       /* Update the linear buffer before presenting the pixmap */
-      draw->ext->image->blitImage(dri_context,
-                                  back->linear_buffer,
-                                  back->image,
-                                  0, 0, back->width,
-                                  back->height,
-                                  0, 0, back->width,
-                                  back->height, __BLIT_FLAG_FLUSH);
-      /* Update the fake front */
-      if (draw->have_fake_front)
-         draw->ext->image->blitImage(dri_context,
-                                     draw->buffers[LOADER_DRI3_FRONT_ID]->image,
-                                     back->image,
-                                     0, 0, draw->width, draw->height,
-                                     0, 0, draw->width, draw->height,
-                                     __BLIT_FLAG_FLUSH);
+      (void) loader_dri3_blit_image(draw,
+                                    back->linear_buffer,
+                                    back->image,
+                                    0, 0, back->width, back->height,
+                                    0, 0, __BLIT_FLAG_FLUSH);
+   }
+
+   /* If we need to preload the new back buffer, remember the source.
+    * The force_copy parameter is used by EGL to attempt to preserve
+    * the back buffer across a call to this function.
+    */
+   if (draw->swap_method != __DRI_ATTRIB_SWAP_UNDEFINED || force_copy)
+      draw->cur_blit_source = LOADER_DRI3_BACK_ID(draw->cur_back);
+
+   /* Exchange the back and fake front. Even though the server knows about these
+    * buffers, it has no notion of back and fake front.
+    */
+   if (back && draw->have_fake_front) {
+      struct loader_dri3_buffer *tmp;
+
+      tmp = dri3_fake_front_buffer(draw);
+      draw->buffers[LOADER_DRI3_FRONT_ID] = back;
+      draw->buffers[LOADER_DRI3_BACK_ID(draw->cur_back)] = tmp;
+
+      if (draw->swap_method == __DRI_ATTRIB_SWAP_COPY  || force_copy)
+         draw->cur_blit_source = LOADER_DRI3_FRONT_ID;
    }
 
    dri3_flush_present_events(draw);
@@ -672,7 +848,7 @@ loader_dri3_swap_buffers_msc(struct loader_dri3_drawable *draw,
        */
       ++draw->send_sbc;
       if (target_msc == 0 && divisor == 0 && remainder == 0)
-         target_msc = draw->msc + swap_interval *
+         target_msc = draw->msc + draw->swap_interval *
                       (draw->send_sbc - draw->recv_sbc);
       else if (divisor == 0 && remainder > 0) {
          /* From the GLX_OML_sync_control spec:
@@ -696,10 +872,15 @@ loader_dri3_swap_buffers_msc(struct loader_dri3_drawable *draw,
        * behaviour by not using XCB_PRESENT_OPTION_ASYNC, but this should not be
        * the default.
        */
-      if (swap_interval == 0)
+      if (draw->swap_interval == 0)
           options |= XCB_PRESENT_OPTION_ASYNC;
-      if (force_copy)
-          options |= XCB_PRESENT_OPTION_COPY;
+
+      /* If we need to populate the new back, but need to reuse the back
+       * buffer slot due to lack of local blit capabilities, make sure
+       * the server doesn't flip and we deadlock.
+       */
+      if (!loader_dri3_have_image_blit(draw) && draw->cur_blit_source != -1)
+         options |= XCB_PRESENT_OPTION_COPY;
 
       back->busy = 1;
       back->last_swap = draw->send_sbc;
@@ -720,27 +901,33 @@ loader_dri3_swap_buffers_msc(struct loader_dri3_drawable *draw,
                          remainder, 0, NULL);
       ret = (int64_t) draw->send_sbc;
 
-      /* If there's a fake front, then copy the source back buffer
-       * to the fake front to keep it up to date. This needs
-       * to reset the fence and make future users block until
-       * the X server is done copying the bits
+      /* Schedule a server-side back-preserving blit if necessary.
+       * This happens iff all conditions below are satisfied:
+       * a) We have a fake front,
+       * b) We need to preserve the back buffer,
+       * c) We don't have local blit capabilities.
        */
-      if (draw->have_fake_front && !draw->is_different_gpu) {
-         dri3_fence_reset(draw->conn, draw->buffers[LOADER_DRI3_FRONT_ID]);
-         dri3_copy_area(draw->conn,
-                        back->pixmap,
-                        draw->buffers[LOADER_DRI3_FRONT_ID]->pixmap,
+      if (!loader_dri3_have_image_blit(draw) && draw->cur_blit_source != -1 &&
+          draw->cur_blit_source != LOADER_DRI3_BACK_ID(draw->cur_back)) {
+         struct loader_dri3_buffer *new_back = dri3_back_buffer(draw);
+         struct loader_dri3_buffer *src = draw->buffers[draw->cur_blit_source];
+
+         dri3_fence_reset(draw->conn, new_back);
+         dri3_copy_area(draw->conn, src->pixmap,
+                        new_back->pixmap,
                         dri3_drawable_gc(draw),
-                        0, 0, 0, 0,
-                        draw->width, draw->height);
-         dri3_fence_trigger(draw->conn, draw->buffers[LOADER_DRI3_FRONT_ID]);
+                        0, 0, 0, 0, draw->width, draw->height);
+         dri3_fence_trigger(draw->conn, new_back);
+         new_back->last_swap = src->last_swap;
       }
+
       xcb_flush(draw->conn);
       if (draw->stamp)
          ++(*draw->stamp);
    }
+   mtx_unlock(&draw->mtx);
 
-   (draw->ext->flush->invalidate)(draw->dri_drawable);
+   draw->ext->flush->invalidate(draw->dri_drawable);
 
    return ret;
 }
@@ -748,15 +935,15 @@ loader_dri3_swap_buffers_msc(struct loader_dri3_drawable *draw,
 int
 loader_dri3_query_buffer_age(struct loader_dri3_drawable *draw)
 {
-   int back_id = LOADER_DRI3_BACK_ID(dri3_find_back(draw));
+   struct loader_dri3_buffer *back = dri3_find_back_alloc(draw);
+   int ret;
 
-   if (back_id < 0 || !draw->buffers[back_id])
-      return 0;
+   mtx_lock(&draw->mtx);
+   ret = (!back || back->last_swap == 0) ? 0 :
+      draw->send_sbc - back->last_swap + 1;
+   mtx_unlock(&draw->mtx);
 
-   if (draw->buffers[back_id]->last_swap != 0)
-      return draw->send_sbc - draw->buffers[back_id]->last_swap + 1;
-   else
-      return 0;
+   return ret;
 }
 
 /** loader_dri3_open
@@ -814,6 +1001,27 @@ dri3_cpp_for_format(uint32_t format) {
    }
 }
 
+/* the DRIimage createImage function takes __DRI_IMAGE_FORMAT codes, while
+ * the createImageFromFds call takes __DRI_IMAGE_FOURCC codes. To avoid
+ * complete confusion, just deal in __DRI_IMAGE_FORMAT codes for now and
+ * translate to __DRI_IMAGE_FOURCC codes in the call to createImageFromFds
+ */
+static int
+image_format_to_fourcc(int format)
+{
+
+   /* Convert from __DRI_IMAGE_FORMAT to __DRI_IMAGE_FOURCC (sigh) */
+   switch (format) {
+   case __DRI_IMAGE_FORMAT_SARGB8: return __DRI_IMAGE_FOURCC_SARGB8888;
+   case __DRI_IMAGE_FORMAT_RGB565: return __DRI_IMAGE_FOURCC_RGB565;
+   case __DRI_IMAGE_FORMAT_XRGB8888: return __DRI_IMAGE_FOURCC_XRGB8888;
+   case __DRI_IMAGE_FORMAT_ARGB8888: return __DRI_IMAGE_FOURCC_ARGB8888;
+   case __DRI_IMAGE_FORMAT_ABGR8888: return __DRI_IMAGE_FOURCC_ABGR8888;
+   case __DRI_IMAGE_FORMAT_XBGR8888: return __DRI_IMAGE_FOURCC_XBGR8888;
+   }
+   return 0;
+}
+
 /** loader_dri3_alloc_render_buffer
  *
  * Use the driver createImage function to construct a __DRIimage, then
@@ -856,34 +1064,34 @@ dri3_alloc_render_buffer(struct loader_dri3_drawable *draw, unsigned int format,
       goto no_image;
 
    if (!draw->is_different_gpu) {
-      buffer->image = (draw->ext->image->createImage)(draw->dri_screen,
-                                                      width, height,
-                                                      format,
-                                                      __DRI_IMAGE_USE_SHARE |
-                                                      __DRI_IMAGE_USE_SCANOUT |
-                                                      __DRI_IMAGE_USE_BACKBUFFER,
-                                                      buffer);
+      buffer->image = draw->ext->image->createImage(draw->dri_screen,
+                                                    width, height,
+                                                    format,
+                                                    __DRI_IMAGE_USE_SHARE |
+                                                    __DRI_IMAGE_USE_SCANOUT |
+                                                    __DRI_IMAGE_USE_BACKBUFFER,
+                                                    buffer);
       pixmap_buffer = buffer->image;
 
       if (!buffer->image)
          goto no_image;
    } else {
-      buffer->image = (draw->ext->image->createImage)(draw->dri_screen,
-                                                      width, height,
-                                                      format,
-                                                      0,
-                                                      buffer);
+      buffer->image = draw->ext->image->createImage(draw->dri_screen,
+                                                    width, height,
+                                                    format,
+                                                    0,
+                                                    buffer);
 
       if (!buffer->image)
          goto no_image;
 
       buffer->linear_buffer =
-        (draw->ext->image->createImage)(draw->dri_screen,
-                                        width, height, format,
-                                        __DRI_IMAGE_USE_SHARE |
-                                        __DRI_IMAGE_USE_LINEAR |
-                                        __DRI_IMAGE_USE_BACKBUFFER,
-                                        buffer);
+        draw->ext->image->createImage(draw->dri_screen,
+                                      width, height, format,
+                                      __DRI_IMAGE_USE_SHARE |
+                                      __DRI_IMAGE_USE_LINEAR |
+                                      __DRI_IMAGE_USE_BACKBUFFER,
+                                      buffer);
       pixmap_buffer = buffer->linear_buffer;
 
       if (!buffer->linear_buffer)
@@ -892,14 +1100,14 @@ dri3_alloc_render_buffer(struct loader_dri3_drawable *draw, unsigned int format,
 
    /* X wants the stride, so ask the image for it
     */
-   if (!(draw->ext->image->queryImage)(pixmap_buffer, __DRI_IMAGE_ATTRIB_STRIDE,
-                                       &stride))
+   if (!draw->ext->image->queryImage(pixmap_buffer, __DRI_IMAGE_ATTRIB_STRIDE,
+                                     &stride))
       goto no_buffer_attrib;
 
    buffer->pitch = stride;
 
-   if (!(draw->ext->image->queryImage)(pixmap_buffer, __DRI_IMAGE_ATTRIB_FD,
-                                       &buffer_fd))
+   if (!draw->ext->image->queryImage(pixmap_buffer, __DRI_IMAGE_ATTRIB_FD,
+                                     &buffer_fd))
       goto no_buffer_attrib;
 
    xcb_dri3_pixmap_from_buffer(draw->conn,
@@ -930,10 +1138,10 @@ dri3_alloc_render_buffer(struct loader_dri3_drawable *draw, unsigned int format,
    return buffer;
 
 no_buffer_attrib:
-   (draw->ext->image->destroyImage)(pixmap_buffer);
+   draw->ext->image->destroyImage(pixmap_buffer);
 no_linear_buffer:
    if (draw->is_different_gpu)
-      (draw->ext->image->destroyImage)(buffer->image);
+      draw->ext->image->destroyImage(buffer->image);
 no_image:
    free(buffer);
 no_buffer:
@@ -953,6 +1161,7 @@ static int
 dri3_update_drawable(__DRIdrawable *driDrawable,
                      struct loader_dri3_drawable *draw)
 {
+   mtx_lock(&draw->mtx);
    if (draw->first_init) {
       xcb_get_geometry_cookie_t                 geom_cookie;
       xcb_get_geometry_reply_t                  *geom_reply;
@@ -993,8 +1202,10 @@ dri3_update_drawable(__DRIdrawable *driDrawable,
 
       geom_reply = xcb_get_geometry_reply(draw->conn, geom_cookie, NULL);
 
-      if (!geom_reply)
+      if (!geom_reply) {
+         mtx_unlock(&draw->mtx);
          return false;
+      }
 
       draw->width = geom_reply->width;
       draw->height = geom_reply->height;
@@ -1026,6 +1237,7 @@ dri3_update_drawable(__DRIdrawable *driDrawable,
       if (error) {
          if (error->error_code != BadWindow) {
             free(error);
+            mtx_unlock(&draw->mtx);
             return false;
          }
          draw->is_pixmap = true;
@@ -1034,30 +1246,10 @@ dri3_update_drawable(__DRIdrawable *driDrawable,
       }
    }
    dri3_flush_present_events(draw);
+   mtx_unlock(&draw->mtx);
    return true;
 }
 
-/* the DRIimage createImage function takes __DRI_IMAGE_FORMAT codes, while
- * the createImageFromFds call takes __DRI_IMAGE_FOURCC codes. To avoid
- * complete confusion, just deal in __DRI_IMAGE_FORMAT codes for now and
- * translate to __DRI_IMAGE_FOURCC codes in the call to createImageFromFds
- */
-static int
-image_format_to_fourcc(int format)
-{
-
-   /* Convert from __DRI_IMAGE_FORMAT to __DRI_IMAGE_FOURCC (sigh) */
-   switch (format) {
-   case __DRI_IMAGE_FORMAT_SARGB8: return __DRI_IMAGE_FOURCC_SARGB8888;
-   case __DRI_IMAGE_FORMAT_RGB565: return __DRI_IMAGE_FOURCC_RGB565;
-   case __DRI_IMAGE_FORMAT_XRGB8888: return __DRI_IMAGE_FOURCC_XRGB8888;
-   case __DRI_IMAGE_FORMAT_ARGB8888: return __DRI_IMAGE_FOURCC_ARGB8888;
-   case __DRI_IMAGE_FORMAT_ABGR8888: return __DRI_IMAGE_FOURCC_ABGR8888;
-   case __DRI_IMAGE_FORMAT_XBGR8888: return __DRI_IMAGE_FOURCC_XBGR8888;
-   }
-   return 0;
-}
-
 __DRIimage *
 loader_dri3_create_image(xcb_connection_t *c,
                          xcb_dri3_buffer_from_pixmap_reply_t *bp_reply,
@@ -1082,19 +1274,19 @@ loader_dri3_create_image(xcb_connection_t *c,
     * we've gotten the planar wrapper, pull the single plane out of it and
     * discard the wrapper.
     */
-   image_planar = (image->createImageFromFds)(dri_screen,
-                                              bp_reply->width,
-                                              bp_reply->height,
-                                              image_format_to_fourcc(format),
-                                              fds, 1,
-                                              &stride, &offset, loaderPrivate);
+   image_planar = image->createImageFromFds(dri_screen,
+                                            bp_reply->width,
+                                            bp_reply->height,
+                                            image_format_to_fourcc(format),
+                                            fds, 1,
+                                            &stride, &offset, loaderPrivate);
    close(fds[0]);
    if (!image_planar)
       return NULL;
 
-   ret = (image->fromPlanar)(image_planar, 0, loaderPrivate);
+   ret = image->fromPlanar(image_planar, 0, loaderPrivate);
 
-   (image->destroyImage)(image_planar);
+   image->destroyImage(image_planar);
 
    return ret;
 }
@@ -1152,7 +1344,7 @@ dri3_get_pixmap_buffer(__DRIdrawable *driDrawable, unsigned int format,
     * no contexts are currently bound. The latter case is at least necessary for
     * obs-studio, when using Window Capture (Xcomposite) as a Source.
     */
-   cur_screen = draw->vtable->get_dri_screen(draw);
+   cur_screen = draw->vtable->get_dri_screen();
    if (!cur_screen) {
        cur_screen = draw->dri_screen;
    }
@@ -1167,7 +1359,6 @@ dri3_get_pixmap_buffer(__DRIdrawable *driDrawable, unsigned int format,
    buffer->own_pixmap = false;
    buffer->width = bp_reply->width;
    buffer->height = bp_reply->height;
-   buffer->buffer_type = buffer_type;
    buffer->shm_fence = shm_fence;
    buffer->sync_fence = sync_fence;
 
@@ -1199,11 +1390,10 @@ dri3_get_buffer(__DRIdrawable *driDrawable,
 {
    struct loader_dri3_buffer *buffer;
    int buf_id;
-   __DRIcontext *dri_context;
-
-   dri_context = draw->vtable->get_dri_context(draw);
 
    if (buffer_type == loader_dri3_buffer_back) {
+      draw->back_format = format;
+
       buf_id = dri3_find_back(draw);
 
       if (buf_id < 0)
@@ -1234,30 +1424,31 @@ dri3_get_buffer(__DRIdrawable *driDrawable,
       /* When resizing, copy the contents of the old buffer, waiting for that
        * copy to complete using our fences before proceeding
        */
-      switch (buffer_type) {
-      case loader_dri3_buffer_back:
-         if (buffer) {
-            if (!buffer->linear_buffer) {
-               dri3_fence_reset(draw->conn, new_buffer);
-               dri3_fence_await(draw->conn, buffer);
-               dri3_copy_area(draw->conn,
-                              buffer->pixmap,
-                              new_buffer->pixmap,
-                              dri3_drawable_gc(draw),
-                              0, 0, 0, 0,
-                              draw->width, draw->height);
-               dri3_fence_trigger(draw->conn, new_buffer);
-            } else if (draw->vtable->in_current_context(draw)) {
-               draw->ext->image->blitImage(dri_context,
-                                           new_buffer->image,
-                                           buffer->image,
-                                           0, 0, draw->width, draw->height,
-                                           0, 0, draw->width, draw->height, 0);
-            }
-            dri3_free_render_buffer(draw, buffer);
+      if ((buffer_type == loader_dri3_buffer_back ||
+           (buffer_type == loader_dri3_buffer_front && draw->have_fake_front))
+          && buffer) {
+
+         /* Fill the new buffer with data from an old buffer */
+         dri3_fence_await(draw->conn, draw, buffer);
+         if (!loader_dri3_blit_image(draw,
+                                     new_buffer->image,
+                                     buffer->image,
+                                     0, 0, draw->width, draw->height,
+                                     0, 0, 0) &&
+             !buffer->linear_buffer) {
+            dri3_fence_reset(draw->conn, new_buffer);
+            dri3_copy_area(draw->conn,
+                           buffer->pixmap,
+                           new_buffer->pixmap,
+                           dri3_drawable_gc(draw),
+                           0, 0, 0, 0,
+                           draw->width, draw->height);
+            dri3_fence_trigger(draw->conn, new_buffer);
          }
-         break;
-      case loader_dri3_buffer_front:
+         dri3_free_render_buffer(draw, buffer);
+      } else if (buffer_type == loader_dri3_buffer_front) {
+         /* Fill the new fake front with data from a real front */
+         loader_dri3_swapbuffer_barrier(draw);
          dri3_fence_reset(draw->conn, new_buffer);
          dri3_copy_area(draw->conn,
                         draw->drawable,
@@ -1267,23 +1458,45 @@ dri3_get_buffer(__DRIdrawable *driDrawable,
                         draw->width, draw->height);
          dri3_fence_trigger(draw->conn, new_buffer);
 
-         if (new_buffer->linear_buffer &&
-             draw->vtable->in_current_context(draw)) {
-            dri3_fence_await(draw->conn, new_buffer);
-            draw->ext->image->blitImage(dri_context,
-                                        new_buffer->image,
-                                        new_buffer->linear_buffer,
-                                        0, 0, draw->width, draw->height,
-                                        0, 0, draw->width, draw->height, 0);
+         if (new_buffer->linear_buffer) {
+            dri3_fence_await(draw->conn, draw, new_buffer);
+            (void) loader_dri3_blit_image(draw,
+                                          new_buffer->image,
+                                          new_buffer->linear_buffer,
+                                          0, 0, draw->width, draw->height,
+                                          0, 0, 0);
          }
-         break;
       }
       buffer = new_buffer;
-      buffer->buffer_type = buffer_type;
       draw->buffers[buf_id] = buffer;
    }
-   dri3_fence_await(draw->conn, buffer);
+   dri3_fence_await(draw->conn, draw, buffer);
 
+   /*
+    * Do we need to preserve the content of a previous buffer?
+    *
+    * Note that this blit is needed only to avoid a wait for a buffer that
+    * is currently in the flip chain or being scanned out from. That's really
+    * a tradeoff. If we're ok with the wait we can reduce the number of back
+    * buffers to 1 for SWAP_EXCHANGE, and 1 for SWAP_COPY,
+    * but in the latter case we must disallow page-flipping.
+    */
+   if (buffer_type == loader_dri3_buffer_back &&
+       draw->cur_blit_source != -1 &&
+       draw->buffers[draw->cur_blit_source] &&
+       buffer != draw->buffers[draw->cur_blit_source]) {
+
+      struct loader_dri3_buffer *source = draw->buffers[draw->cur_blit_source];
+
+      /* Avoid flushing here. Will propably do good for tiling hardware. */
+      (void) loader_dri3_blit_image(draw,
+                                    buffer->image,
+                                    source->image,
+                                    0, 0, draw->width, draw->height,
+                                    0, 0, 0);
+      buffer->last_swap = source->last_swap;
+      draw->cur_blit_source = -1;
+   }
    /* Return the requested buffer */
    return buffer;
 }
@@ -1307,10 +1520,12 @@ dri3_free_buffers(__DRIdrawable *driDrawable,
    case loader_dri3_buffer_back:
       first_id = LOADER_DRI3_BACK_ID(0);
       n_id = LOADER_DRI3_MAX_BACK;
+      draw->cur_blit_source = -1;
       break;
    case loader_dri3_buffer_front:
       first_id = LOADER_DRI3_FRONT_ID;
-      n_id = 1;
+      /* Don't free a fake front holding new backbuffer content. */
+      n_id = (draw->cur_blit_source == LOADER_DRI3_FRONT_ID) ? 0 : 1;
    }
 
    for (buf_id = first_id; buf_id < first_id + n_id; buf_id++) {
@@ -1349,8 +1564,10 @@ loader_dri3_get_buffers(__DRIdrawable *driDrawable,
    if (!dri3_update_drawable(driDrawable, draw))
       return false;
 
-   /* pixmaps always have front buffers */
-   if (draw->is_pixmap)
+   /* pixmaps always have front buffers.
+    * Exchange swaps also mandate fake front buffers.
+    */
+   if (draw->is_pixmap || draw->swap_method == __DRI_ATTRIB_SWAP_EXCHANGE)
       buffer_mask |= __DRI_IMAGE_BUFFER_FRONT;
 
    if (buffer_mask & __DRI_IMAGE_BUFFER_FRONT) {
@@ -1427,7 +1644,93 @@ loader_dri3_update_drawable_geometry(struct loader_dri3_drawable *draw)
       draw->width = geom_reply->width;
       draw->height = geom_reply->height;
       draw->vtable->set_drawable_size(draw, draw->width, draw->height);
+      draw->ext->flush->invalidate(draw->dri_drawable);
 
       free(geom_reply);
    }
 }
+
+
+/**
+ * Make sure the server has flushed all pending swap buffers to hardware
+ * for this drawable. Ideally we'd want to send an X protocol request to
+ * have the server block our connection until the swaps are complete. That
+ * would avoid the potential round-trip here.
+ */
+void
+loader_dri3_swapbuffer_barrier(struct loader_dri3_drawable *draw)
+{
+   int64_t ust, msc, sbc;
+
+   (void) loader_dri3_wait_for_sbc(draw, 0, &ust, &msc, &sbc);
+}
+
+/**
+ * Perform any cleanup associated with a close screen operation.
+ * \param dri_screen[in,out] Pointer to __DRIscreen about to be closed.
+ *
+ * This function destroys the screen's cached swap context if any.
+ */
+void
+loader_dri3_close_screen(__DRIscreen *dri_screen)
+{
+   mtx_lock(&blit_context.mtx);
+   if (blit_context.ctx && blit_context.cur_screen == dri_screen) {
+      blit_context.core->destroyContext(blit_context.ctx);
+      blit_context.ctx = NULL;
+   }
+   mtx_unlock(&blit_context.mtx);
+}
+
+/**
+ * Find a backbuffer slot - potentially allocating a back buffer
+ *
+ * \param draw[in,out]  Pointer to the drawable for which to find back.
+ * \return Pointer to a new back buffer or NULL if allocation failed or was
+ * not mandated.
+ *
+ * Find a potentially new back buffer, and if it's not been allocated yet and
+ * in addition needs initializing, then try to allocate and initialize it.
+ */
+#include <stdio.h>
+static struct loader_dri3_buffer *
+dri3_find_back_alloc(struct loader_dri3_drawable *draw)
+{
+   struct loader_dri3_buffer *back;
+   int id;
+
+   id = dri3_find_back(draw);
+   if (id < 0)
+      return NULL;
+
+   back = draw->buffers[id];
+   /* Allocate a new back if we haven't got one */
+   if (!back && draw->back_format != __DRI_IMAGE_FORMAT_NONE &&
+       dri3_update_drawable(draw->dri_drawable, draw))
+      back = dri3_alloc_render_buffer(draw, draw->back_format,
+                                      draw->width, draw->height, draw->depth);
+
+   if (!back)
+      return NULL;
+
+   draw->buffers[id] = back;
+
+   /* If necessary, prefill the back with data according to swap_method mode. */
+   if (draw->cur_blit_source != -1 &&
+       draw->buffers[draw->cur_blit_source] &&
+       back != draw->buffers[draw->cur_blit_source]) {
+      struct loader_dri3_buffer *source = draw->buffers[draw->cur_blit_source];
+
+      dri3_fence_await(draw->conn, draw, source);
+      dri3_fence_await(draw->conn, draw, back);
+      (void) loader_dri3_blit_image(draw,
+                                    back->image,
+                                    source->image,
+                                    0, 0, draw->width, draw->height,
+                                    0, 0, 0);
+      back->last_swap = source->last_swap;
+      draw->cur_blit_source = -1;
+   }
+
+   return back;
+}
diff --git a/lib/mesa/src/loader/loader_dri3_helper.h b/lib/mesa/src/loader/loader_dri3_helper.h
index a865e4635..790f78427 100644
--- a/lib/mesa/src/loader/loader_dri3_helper.h
+++ b/lib/mesa/src/loader/loader_dri3_helper.h
@@ -33,6 +33,7 @@
 
 #include <GL/gl.h>
 #include <GL/internal/dri_interface.h>
+#include <c11/threads.h>
 
 enum loader_dri3_buffer_type {
    loader_dri3_buffer_back = 0,
@@ -67,8 +68,6 @@ struct loader_dri3_buffer {
    uint32_t     flags;
    uint32_t     width, height;
    uint64_t     last_swap;
-
-   enum loader_dri3_buffer_type        buffer_type;
 };
 
 
@@ -97,13 +96,10 @@ struct loader_dri3_extensions {
 struct loader_dri3_drawable;
 
 struct loader_dri3_vtable {
-   int (*get_swap_interval)(struct loader_dri3_drawable *);
-   int (*clamp_swap_interval)(struct loader_dri3_drawable *, int);
-   void (*set_swap_interval)(struct loader_dri3_drawable *, int);
    void (*set_drawable_size)(struct loader_dri3_drawable *, int, int);
    bool (*in_current_context)(struct loader_dri3_drawable *);
    __DRIcontext *(*get_dri_context)(struct loader_dri3_drawable *);
-   __DRIscreen *(*get_dri_screen)(struct loader_dri3_drawable *);
+   __DRIscreen *(*get_dri_screen)(void);
    void (*flush_drawable)(struct loader_dri3_drawable *, unsigned);
    void (*show_fps)(struct loader_dri3_drawable *, uint64_t);
 };
@@ -149,6 +145,7 @@ struct loader_dri3_drawable {
    struct loader_dri3_buffer *buffers[LOADER_DRI3_NUM_BUFFERS];
    int cur_back;
    int num_back;
+   int cur_blit_source;
 
    uint32_t *stamp;
 
@@ -157,9 +154,22 @@ struct loader_dri3_drawable {
    xcb_special_event_t *special_event;
 
    bool first_init;
+   int swap_interval;
 
    struct loader_dri3_extensions *ext;
    const struct loader_dri3_vtable *vtable;
+
+   unsigned int swap_method;
+   unsigned int back_format;
+
+   /* Currently protects the following fields:
+    * event_cnd, has_event_waiter,
+    * recv_sbc, ust, msc, recv_msc_serial,
+    * notify_ust, notify_msc
+    */
+   mtx_t mtx;
+   cnd_t event_cnd;
+   bool has_event_waiter;
 };
 
 void
@@ -241,4 +251,10 @@ loader_dri3_get_buffers(__DRIdrawable *driDrawable,
 
 void
 loader_dri3_update_drawable_geometry(struct loader_dri3_drawable *draw);
+
+void
+loader_dri3_swapbuffer_barrier(struct loader_dri3_drawable *draw);
+
+void
+loader_dri3_close_screen(__DRIscreen *dri_screen);
 #endif