The window buffer mechanism would free the pixmap and its corresponding
Wayland buffer as soon as window buffers are disposed.
Typically when the X11 window is unrealized, the current window buffer
is still used by the Wayland compositor and yet Xwayland will destroy
the buffer.
As a matter of fact, Xwayland should not destroy the Wayland buffer
before the wl_buffer.release event is received.
Add a reference counter to the window buffer similar to the to pixmap
reference counter to keep the buffer around until the release callback
is received.
Increase that reference counter on the buffer which will be attached to
the surface, and drop that reference when receiving the release callback
notification.
v2: Use a specific reference counter on the buffer rather than relying
on the pixmap refcnt (Michel Dänzer <mdaenzer@redhat.com>)
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
Acked-by: Martin Peres <martin.peres@mupuf.org>
Using multiple window buffers crashes with EGLStream, which does not
need it anyway as this is handled through EGL directly.
Add a flag to the EGL backend to indicate whether it would benefit from
multiple buffers and use this in the get_buffer() function.
Thanks to Adam Jackson <ajax@redhat.com> for pointing out that issue
with EGLStream.
v2: Fix logical test (Adam Jackson <ajax@redhat.com>)
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Move Xwayland screen related code to a separate source file and header.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
Move Xwayland generic pixmap code to a separate source file and header.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
Over time, Xwayland main source file `xwayland.c` has grown in size
which makes it look cluttered and harder to read.
Move the code dealing with Xwayland window to its own source and header
files.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
Damage coordinates are relative to the drawable, (0,0) being the top
left corner inside the border.
Therefore, when applying damages or accumulating damages between window
buffers, we need to take the window border width into account as well,
otherwise the updates might be only partial or misplaced.
Related: https://gitlab.freedesktop.org/xorg/xserver/issues/951
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
Add a mechanism to create, recycle and destroy window buffers when
needed.
Typically, this adds a new `xwl_window_buffer` structure which
represents a buffer for a given Xwayland window.
Each Xwayland window has two different pools of buffers:
- The available buffers pool:
Those are buffers which where created previously and that have either
not been submitted to the compositor or submitted and released.
- The unavailable buffers pool:
Those are typically the buffers which are being used by the
compositor, awaiting a release.
Initially, an Xwayland window starts with both pools empty. As soon as a
new buffer is needed, it's either created (if there is none available)
or picked from the pool of available buffers.
Once submitted to the compositor, the buffer is moved to the pool of
unavailable buffers. When the corresponding `wl_buffer` is released by
the compositor, it is moved back to pool of available buffers again to
be reused when needed.
To avoid keeping too many buffers around doing nothing, a garbage
collection of older, unused buffers also takes care of disposing the
buffers being unused for some time.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
