xserver-multidpi/hw/xwayland/xwayland-glamor.c
Lyude Paul 54ac09717c xwayland: Add glamor egl_backend for EGLStreams
This adds initial support for displaying Xwayland applications through
the use of EGLStreams and nvidia's custom wayland protocol by adding
another egl_backend driver. This also adds some additional egl_backend
hooks that are required to make things work properly.

EGLStreams work a lot differently then the traditional way of handling
buffers with wayland. Unfortunately, there are also a LOT of various
pitfalls baked into it's design that need to be explained.

This has a very large and unfortunate implication: direct rendering is,
for the time being at least, impossible to do through EGLStreams. The
main reason being that the EGLStream spec mandates that we lose the
entire color buffer contents with each eglSwapBuffers(), which goes
against X's requirement of not losing data with pixmaps.  no way to use
an allocated EGLSurface as the storage for glamor rendering like we do
with GBM, we have to rely on blitting each pixmap to it's respective
EGLSurface producer each frame. In order to pull this off, we add two
different additional egl_backend hooks that GBM opts out of
implementing:

- egl_backend.allow_commits for holding off displaying any EGLStream
  backed pixmaps until the point where it's stream is completely
  initialized and ready for use
- egl_backend.post_damage for blitting the content of the EGLStream
  surface producer before Xwayland actually damages and commits the
  wl_surface to the screen.

The other big pitfall here is that using nvidia's wayland-eglstreams
helper library is also not possible for the most part. All of it's API
for creating and destroying streams rely on being able to perform a
roundtrip in order to bring each stream to completion since the wayland
compositor must perform it's job of connecting a consumer to each
EGLstream. Because Xwayland has to potentially handle both responding to
the wayland compositor and it's own X clients, the situation of the
wayland compositor being one of our X clients must be considered. If we
perform a roundtrip with the Wayland compositor, it's possible that the
wayland compositor might currently be connected to us as an X client and
thus hang while both Xwayland and the wayland compositor await responses
from eachother. To avoid this, we work directly with the wayland
protocol and use wl_display_sync() events along with release() events to
set up and destroy EGLStreams asynchronously alongside handling X
clients.

Additionally, since setting up EGLStreams is not an atomic operation we
have to take into consideration the fact that an EGLStream can
potentially be created in response to a window resize, then immediately
deleted due to another pending window resize in the same X client's
pending reqests before Xwayland hits the part of it's event loop where
we read from the wayland compositor. To make this even more painful, we
also have to take into consideration that since EGLStreams are not
atomic that it's possible we could delete wayland resources for an
EGLStream before the compositor even finishes using them and thus run
into errors. So, we use quite a bit of tracking logic to keep EGLStream
objects alive until we know the compositor isn't using them (even if
this means the stream outlives the pixmap it backed).

While the default backend for glamor remains GBM, this patch exists for
users who have had to deal with the reprecussion of their GPU
manufacturers ignoring the advice of upstream and the standardization of
GBM across most major GPU manufacturers. It is not intended to be a
final solution to the GBM debate, but merely a baindaid so our users
don't have to suffer from the consequences of companies avoiding working
upstream. New drivers are strongly encouraged not to use this as a
backend, and use GBM like everyone else. We even spit this out as an
error from Xwayland when using the eglstream backend.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
2018-04-24 16:51:18 -04:00

269 lines
7.8 KiB
C

/*
* Copyright © 2011-2014 Intel Corporation
*
* Permission to use, copy, modify, distribute, and sell this software
* and its documentation for any purpose is hereby granted without
* fee, provided that the above copyright notice appear in all copies
* and that both that copyright notice and this permission notice
* appear in supporting documentation, and that the name of the
* copyright holders not be used in advertising or publicity
* pertaining to distribution of the software without specific,
* written prior permission. The copyright holders make no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied
* warranty.
*
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
* SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*/
#include "xwayland.h"
#define MESA_EGL_NO_X11_HEADERS
#include <glamor_egl.h>
#include <glamor.h>
#include <glamor_context.h>
static void
glamor_egl_make_current(struct glamor_context *glamor_ctx)
{
eglMakeCurrent(glamor_ctx->display, EGL_NO_SURFACE,
EGL_NO_SURFACE, EGL_NO_CONTEXT);
if (!eglMakeCurrent(glamor_ctx->display,
EGL_NO_SURFACE, EGL_NO_SURFACE,
glamor_ctx->ctx))
FatalError("Failed to make EGL context current\n");
}
void
xwl_glamor_egl_make_current(struct xwl_screen *xwl_screen)
{
if (lastGLContext == xwl_screen->glamor_ctx)
return;
lastGLContext = xwl_screen->glamor_ctx;
xwl_screen->glamor_ctx->make_current(xwl_screen->glamor_ctx);
}
Bool
xwl_glamor_egl_supports_device_probing(void)
{
return epoxy_has_egl() &&
epoxy_has_egl_extension(NULL, "EGL_EXT_device_base");
}
void **
xwl_glamor_egl_get_devices(int *num_devices)
{
#ifdef XWL_HAS_EGLSTREAM
EGLDeviceEXT *devices;
Bool ret;
int drm_dev_count = 0;
int i;
/* Get the number of devices */
ret = eglQueryDevicesEXT(0, NULL, num_devices);
if (!ret || *num_devices < 1)
return NULL;
devices = calloc(*num_devices, sizeof(EGLDeviceEXT));
if (!devices)
return NULL;
ret = eglQueryDevicesEXT(*num_devices, devices, num_devices);
if (!ret)
goto error;
/* We're only ever going to care about devices that support
* EGL_EXT_device_drm, so filter out the ones that don't
*/
for (i = 0; i < *num_devices; i++) {
const char *extension_str =
eglQueryDeviceStringEXT(devices[i], EGL_EXTENSIONS);
if (!epoxy_extension_in_string(extension_str, "EGL_EXT_device_drm"))
continue;
devices[drm_dev_count++] = devices[i];
}
if (!drm_dev_count)
goto error;
*num_devices = drm_dev_count;
devices = realloc(devices, sizeof(EGLDeviceEXT) * drm_dev_count);
return devices;
error:
free(devices);
#endif
return NULL;
}
Bool
xwl_glamor_egl_device_has_egl_extensions(void *device,
const char **ext_list, size_t size)
{
EGLDisplay egl_display;
int i;
Bool has_exts = TRUE;
egl_display = glamor_egl_get_display(EGL_PLATFORM_DEVICE_EXT, device);
if (!egl_display || !eglInitialize(egl_display, NULL, NULL))
return FALSE;
for (i = 0; i < size; i++) {
if (!epoxy_has_egl_extension(egl_display, ext_list[i])) {
has_exts = FALSE;
break;
}
}
eglTerminate(egl_display);
return has_exts;
}
void
glamor_egl_screen_init(ScreenPtr screen, struct glamor_context *glamor_ctx)
{
struct xwl_screen *xwl_screen = xwl_screen_get(screen);
glamor_ctx->ctx = xwl_screen->egl_context;
glamor_ctx->display = xwl_screen->egl_display;
glamor_ctx->make_current = glamor_egl_make_current;
xwl_screen->glamor_ctx = glamor_ctx;
}
void
xwl_glamor_init_wl_registry(struct xwl_screen *xwl_screen,
struct wl_registry *registry,
uint32_t id, const char *interface,
uint32_t version)
{
if (xwl_screen->egl_backend.init_wl_registry)
xwl_screen->egl_backend.init_wl_registry(xwl_screen, registry,
interface, id, version);
}
struct wl_buffer *
xwl_glamor_pixmap_get_wl_buffer(PixmapPtr pixmap,
unsigned short width,
unsigned short height,
Bool *created)
{
struct xwl_screen *xwl_screen = xwl_screen_get(pixmap->drawable.pScreen);
if (xwl_screen->egl_backend.get_wl_buffer_for_pixmap)
return xwl_screen->egl_backend.get_wl_buffer_for_pixmap(pixmap,
width,
height,
created);
return NULL;
}
void
xwl_glamor_post_damage(struct xwl_window *xwl_window,
PixmapPtr pixmap, RegionPtr region)
{
struct xwl_screen *xwl_screen = xwl_window->xwl_screen;
if (xwl_screen->egl_backend.post_damage)
xwl_screen->egl_backend.post_damage(xwl_window, pixmap, region);
}
Bool
xwl_glamor_allow_commits(struct xwl_window *xwl_window)
{
struct xwl_screen *xwl_screen = xwl_window->xwl_screen;
if (xwl_screen->egl_backend.allow_commits)
return xwl_screen->egl_backend.allow_commits(xwl_window);
else
return TRUE;
}
static Bool
xwl_glamor_create_screen_resources(ScreenPtr screen)
{
struct xwl_screen *xwl_screen = xwl_screen_get(screen);
int ret;
screen->CreateScreenResources = xwl_screen->CreateScreenResources;
ret = (*screen->CreateScreenResources) (screen);
xwl_screen->CreateScreenResources = screen->CreateScreenResources;
screen->CreateScreenResources = xwl_glamor_create_screen_resources;
if (!ret)
return ret;
if (xwl_screen->rootless) {
screen->devPrivate =
fbCreatePixmap(screen, 0, 0, screen->rootDepth, 0);
}
else {
screen->devPrivate = screen->CreatePixmap(
screen, screen->width, screen->height, screen->rootDepth,
CREATE_PIXMAP_USAGE_BACKING_PIXMAP);
}
SetRootClip(screen, xwl_screen->root_clip_mode);
return screen->devPrivate != NULL;
}
int
glamor_egl_fd_name_from_pixmap(ScreenPtr screen,
PixmapPtr pixmap,
CARD16 *stride, CARD32 *size)
{
return 0;
}
Bool
xwl_glamor_init(struct xwl_screen *xwl_screen)
{
ScreenPtr screen = xwl_screen->screen;
const char *no_glamor_env;
no_glamor_env = getenv("XWAYLAND_NO_GLAMOR");
if (no_glamor_env && *no_glamor_env != '0') {
ErrorF("Disabling glamor and dri3 support, XWAYLAND_NO_GLAMOR is set\n");
return FALSE;
}
if (!xwl_screen->egl_backend.init_egl(xwl_screen)) {
ErrorF("EGL setup failed, disabling glamor\n");
return FALSE;
}
if (!glamor_init(xwl_screen->screen, GLAMOR_USE_EGL_SCREEN)) {
ErrorF("Failed to initialize glamor\n");
return FALSE;
}
if (!xwl_screen->egl_backend.init_screen(xwl_screen)) {
ErrorF("EGL backend init_screen() failed, disabling glamor\n");
return FALSE;
}
xwl_screen->CreateScreenResources = screen->CreateScreenResources;
screen->CreateScreenResources = xwl_glamor_create_screen_resources;
#ifdef XV
if (!xwl_glamor_xv_init(screen))
ErrorF("Failed to initialize glamor Xv extension\n");
#endif
return TRUE;
}