Use dma-bufs for screensharing only when client asks for it

kwin-use-dmabufs-only-when-client-asks-for-it.patch

@@ -0,0 +1,55 @@
+From caaabf84df3aaf96eb0fcccc8c17baefe97826b5 Mon Sep 17 00:00:00 2001
+From: Jan Grulich <jgrulich@redhat.com>
+Date: Wed, 5 May 2021 10:01:49 +0200
+Subject: [PATCH] Screencast: use dma-bufs only when client explicitly asks for
+ it
+
+---
+ src/plugins/screencast/pipewirestream.cpp | 12 ++++++++++--
+ 1 file changed, 10 insertions(+), 2 deletions(-)
+
+diff --git a/src/plugins/screencast/pipewirestream.cpp b/src/plugins/screencast/pipewirestream.cpp
+index 8f9ed30e0..1e86f8b81 100644
+--- a/src/plugins/screencast/pipewirestream.cpp
++++ b/src/plugins/screencast/pipewirestream.cpp
+@@ -106,13 +106,16 @@ void PipeWireStream::onStreamParamChanged(void *data, uint32_t id, const struct
+
+ void PipeWireStream::onStreamAddBuffer(void *data, pw_buffer *buffer)
+ {
++    QSharedPointer<DmaBufTexture> dmabuf;
+     PipeWireStream *stream = static_cast<PipeWireStream *>(data);
+     struct spa_data *spa_data = buffer->buffer->datas;
+
+     spa_data->mapoffset = 0;
+     spa_data->flags = SPA_DATA_FLAG_READWRITE;
+
+-    QSharedPointer<DmaBufTexture> dmabuf(kwinApp()->platform()->createDmaBufTexture(stream->m_resolution));
++    if (spa_data[0].type != SPA_ID_INVALID && spa_data[0].type & (1 << SPA_DATA_DmaBuf))
++        dmabuf.reset(kwinApp()->platform()->createDmaBufTexture(stream->m_resolution));
++
+     if (dmabuf) {
+       spa_data->type = SPA_DATA_DmaBuf;
+       spa_data->fd = dmabuf->fd();
+@@ -122,6 +125,11 @@ void PipeWireStream::onStreamAddBuffer(void *data, pw_buffer *buffer)
+       stream->m_dmabufDataForPwBuffer.insert(buffer, dmabuf);
+ #ifdef F_SEAL_SEAL //Disable memfd on systems that don't have it, like BSD < 12
+     } else {
++        if (!(spa_data[0].type & (1 << SPA_DATA_MemFd))) {
++            qCCritical(KWIN_SCREENCAST) << "memfd: Client doesn't support memfd buffer data type";
++            return;
++        }
++
+         const int bytesPerPixel = stream->m_hasAlpha ? 4 : 3;
+         const int stride = SPA_ROUND_UP_N (stream->m_resolution.width() * bytesPerPixel, 4);
+         spa_data->maxsize = stride * stream->m_resolution.height();
+@@ -341,7 +349,7 @@ void PipeWireStream::recordFrame(GLTexture *frameTexture, const QRegion &damaged
+
+     const auto size = frameTexture->size();
+     spa_data->chunk->offset = 0;
+-    if (data) {
++    if (data || spa_data[0].type == SPA_DATA_MemFd) {
+         const int bpp = data && !m_hasAlpha ? 3 : 4;
+         const uint stride = SPA_ROUND_UP_N (size.width() * bpp, 4);
+         const uint bufferSize = stride * size.height();
+--
+GitLab

kwin.spec

@@ -17,7 +17,7 @@
 
 Name:    kwin
 Version: 5.21.5
-Release: 1%{?dist}
+Release: 2%{?dist}
 Summary: KDE Window manager
 
 # all sources are effectively GPLv2+, except for:
@@ -37,6 +37,7 @@ URL:     https://userbase.kde.org/KWin
 Source0: http://download.kde.org/%{stable}/plasma/%{version}/%{name}-%{version}.tar.xz
 
 ## upstream patches
+Patch0: kwin-use-dmabufs-only-when-client-asks-for-it.patch
 
 ## proposed patches
 
@@ -360,6 +361,9 @@ make test ARGS="--output-on-failure --timeout 10" -C %{_target_platform} ||:
 
 
 %changelog
+* Wed May 05 2021 Jan Grulich <jgrulich@redhat.com> - 5.21.5-2
+- Use dma-bufs for screensharing only when client asks for it
+
 * Tue May 04 2021 Jan Grulich <jgrulich@redhat.com> - 5.21.5-1
 - 5.21.5