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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
Xext meson: Ensure we always build Xext/hashtable.c for glx 2018-04-19 16:20:22 -04:00
Xi Use ARRAY_SIZE all over the tree 2017-10-30 13:45:20 -04:00
composite meson: Distribute more SDK headers 2018-04-02 13:42:08 -04:00
config meson: Fix install path for 10-quirks.conf 2018-03-27 10:28:33 -04:00
damageext Use ARRAY_SIZE all over the tree 2017-10-30 13:45:20 -04:00
dbe meson: Distribute more SDK headers 2018-04-02 13:42:08 -04:00
dix dix: Allow an extension to disable itself 2018-04-24 14:36:04 -04:00
doc Rewrite the byte swapping macros. 2017-04-25 15:01:23 -07:00
dri3 dri3: Fix dri3_buffers_from_pixmap request. 2018-04-17 10:24:42 -04:00
exa exa: promise not to touch the data when swapping pointers 2018-03-21 11:22:59 -04:00
fb meson: Distribute more SDK headers 2018-04-02 13:42:08 -04:00
glamor glamor: fix glamor_xv_query_image_attributes() for odd-width images 2018-04-17 17:30:16 -04:00
glx glx: Require depth > 12 for GLX visuals 2018-04-24 14:36:04 -04:00
hw xwayland: Add glamor egl_backend for EGLStreams 2018-04-24 16:51:18 -04:00
include xwayland: Add glamor egl_backend for EGLStreams 2018-04-24 16:51:18 -04:00
m4 Add ax_pthread.m4 to m4/ 2016-05-29 19:20:51 -07:00
man man: s/__/@/g 2018-03-27 10:13:17 -04:00
mi mi: Hush an almost certainly bogus warning 2018-04-05 14:18:49 -04:00
miext meson: Distribute more SDK headers 2018-04-02 13:42:08 -04:00
os os/WaitFor: Check timers on every iteration 2018-04-17 16:30:36 -04:00
present meson: Distribute more SDK headers 2018-04-02 13:42:08 -04:00
pseudoramiX Unvalidated lengths 2017-10-10 23:33:34 +02:00
randr meson: Distribute more SDK headers 2018-04-02 13:42:08 -04:00
record Add a Meson build system alongside autotools. 2017-04-26 15:25:27 -07:00
render animcur: Fix crash when removing a master device 2018-04-24 14:28:27 -04:00
test travis: Bump rawhide image 2018-03-21 12:11:23 -04:00
xfixes xfixes: Restore monitoring of animated cursors 2018-02-14 13:52:45 -05:00
xkb xkb: Silence some compiler warnings 2018-04-05 14:18:47 -04:00
.appveyor.yml appveyor: use meson 2018-03-21 10:16:44 -04:00
.dir-locals.el Add .dir-locals.el 2013-08-17 12:17:36 +02:00
.gitignore .gitignore: Add new autotools file 'test-driver' 2014-04-21 13:41:42 -07:00
.travis.yml travis: Drop Xcode 8.2 2018-03-21 12:15:28 -04:00
COPYING modesetting: Merge modesetting's COPYING into the xserver's. 2014-09-15 12:46:02 -07:00
Makefile.am automake: Fix 'make dist' 2018-03-28 15:11:16 -04:00
README README: Add link to fd.o CoC 2017-04-11 08:51:34 -04:00
autogen.sh autogen: Set a default subject prefix for patches 2016-02-08 17:41:38 -05:00
configure.ac xwayland: Add glamor egl_backend for EGLStreams 2018-04-24 16:51:18 -04:00
devbook.am doc: Create a script to filter xmlto output 2015-01-05 14:24:06 -08:00
docbook.am docbook.am: embed css styles inside the HTML HEAD element 2011-09-21 14:07:49 -07:00
fix-miregion Change region implementation names to eliminate the 'mi' prefix 2010-06-05 17:47:32 -07:00
fix-miregion-private Change region implementation names to eliminate the 'mi' prefix 2010-06-05 17:47:32 -07:00
fix-patch-whitespace Rename region macros to eliminate screen argument 2010-06-05 18:59:00 -07:00
fix-region Rename region macros to eliminate screen argument 2010-06-05 18:59:00 -07:00
manpages.am autotools: Fix excessive \-escaping that broke the build 2018-03-27 10:47:05 -04:00
meson.build xwayland: Add glamor egl_backend for EGLStreams 2018-04-24 16:51:18 -04:00
meson_options.txt xwayland: Add glamor egl_backend for EGLStreams 2018-04-24 16:51:18 -04:00
xorg-server.m4 macros: clarify documentation 2012-11-05 13:24:57 -06:00
xorg-server.pc.in xfree86: link modules against Xorg symbols on Cygwin 2012-04-05 21:57:07 -05:00
xserver.ent.in doc: relocate xserver.ent in the package root directory 2011-05-14 11:22:26 -07:00

README

					X Server

The X server accepts requests from client applications to create windows,
which are (normally rectangular) "virtual screens" that the client program
can draw into.

Windows are then composed on the actual screen by the X server
(or by a separate composite manager) as directed by the window manager,
which usually communicates with the user via graphical controls such as buttons
and draggable titlebars and borders.

For a comprehensive overview of X Server and X Window System, consult the
following article:
https://en.wikipedia.org/wiki/X_server

All questions regarding this software should be directed at the
Xorg mailing list:

        https://lists.freedesktop.org/mailman/listinfo/xorg

Please submit bug reports to the Xorg bugzilla:

        https://bugs.freedesktop.org/enter_bug.cgi?product=xorg

The master development code repository can be found at:

        git://anongit.freedesktop.org/git/xorg/xserver

        https://cgit.freedesktop.org/xorg/xserver

For patch submission instructions, see:

	https://www.x.org/wiki/Development/Documentation/SubmittingPatches

For more information on the git code manager, see:

        https://wiki.x.org/wiki/GitPage

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Code of Conduct, based on the Contributor Covenant. Please conduct
yourself in a respectful and civilized manner when using the above
mailing lists, bug trackers, etc:

	https://www.freedesktop.org/wiki/CodeOfConduct