Add FUSE io_uring toggle and update libfuse

3 files changed, 195 insertions, 6 deletions

diff --git a/src/src/settingsdialog.ui b/src/src/settingsdialog.ui
index a7e2a90..50c47e0 100644
--- a/src/src/settingsdialog.ui
+++ b/src/src/settingsdialog.ui
@@ -1832,28 +1832,38 @@ If you disable this feature, MO will only display official DLCs this way. Please
             </property>
            </widget>
           </item>
-          <item row="5" column="0">
+          <item row="5" column="0" colspan="4">
+           <widget class="QCheckBox" name="fuseIoUringCheckBox">
+            <property name="toolTip">
+             <string>Enable the kernel FUSE io_uring transport for new VFS mounts. Requires administrator authentication and a VFS remount; Fluorine falls back automatically when unsupported.</string>
+            </property>
+            <property name="text">
+             <string>Enable FUSE io_uring</string>
+            </property>
+           </widget>
+          </item>
+          <item row="6" column="0">
            <widget class="QLabel" name="label_64">
             <property name="text">
              <string>Status:</string>
             </property>
            </widget>
           </item>
-          <item row="5" column="1" colspan="3">
+          <item row="6" column="1" colspan="3">
            <widget class="QLabel" name="protonStatusLabel">
             <property name="text">
              <string>No Prefix</string>
             </property>
            </widget>
           </item>
-          <item row="6" column="0" colspan="4">
+          <item row="7" column="0" colspan="4">
            <widget class="QProgressBar" name="protonProgressBar">
             <property name="value">
              <number>0</number>
             </property>
            </widget>
           </item>
-          <item row="7" column="0" colspan="4">
+          <item row="8" column="0" colspan="4">
            <widget class="QPushButton" name="toggleInstallLog">
             <property name="text">
              <string>Show Install Log</string>
@@ -1866,7 +1876,7 @@ If you disable this feature, MO will only display official DLCs this way. Please
             </property>
            </widget>
           </item>
-          <item row="8" column="0" colspan="4">
+          <item row="9" column="0" colspan="4">
            <widget class="QTextEdit" name="nakInstallLog">
             <property name="readOnly">
              <bool>true</bool>
diff --git a/src/src/settingsdialogproton.cpp b/src/src/settingsdialogproton.cpp
index 896bcb9..fdb8cbd 100644
--- a/src/src/settingsdialogproton.cpp
+++ b/src/src/settingsdialogproton.cpp
@@ -11,6 +11,7 @@
 #include "steamdetection.h"
 #include "slrmanager.h"
 #include <atomic>
+#include <QCheckBox>
 #include <QComboBox>
 #include <QCoreApplication>
 #include <QDateTime>
@@ -26,15 +27,120 @@
 #include <QFutureWatcher>
 #include <QMetaObject>
 #include <QProcess>
+#include <QProcessEnvironment>
 #include <QProgressDialog>
 #include <QSettings>
 #include <QScopeGuard>
 #include <QStandardPaths>
+#include <QSignalBlocker>
 #include <QVBoxLayout>
 
 namespace
 {
 std::atomic<ProtonSettingsTab*> g_activeInstallTab = nullptr;
+
+constexpr const char* kFuseIoUringParameter =
+    "/sys/module/fuse/parameters/enable_uring";
+
+enum class FuseIoUringState
+{
+  Unsupported,
+  Disabled,
+  Enabled,
+  Unknown
+};
+
+FuseIoUringState readFuseIoUringState()
+{
+  QFile parameter(QString::fromUtf8(kFuseIoUringParameter));
+  if (!parameter.exists()) {
+    return FuseIoUringState::Unsupported;
+  }
+
+  if (!parameter.open(QIODevice::ReadOnly | QIODevice::Text)) {
+    return FuseIoUringState::Unknown;
+  }
+
+  const QByteArray value = parameter.readAll().trimmed().toUpper();
+  if (value == "Y" || value == "1") {
+    return FuseIoUringState::Enabled;
+  }
+  if (value == "N" || value == "0") {
+    return FuseIoUringState::Disabled;
+  }
+
+  return FuseIoUringState::Unknown;
+}
+
+QString findPrivilegeHelper(QStringList* arguments)
+{
+  const QString command =
+      QStringLiteral("printf Y > %1").arg(QString::fromUtf8(kFuseIoUringParameter));
+
+  const QString pkexec = QStandardPaths::findExecutable(QStringLiteral("pkexec"));
+  if (!pkexec.isEmpty()) {
+    *arguments = {QStringLiteral("/bin/sh"), QStringLiteral("-c"), command};
+    return pkexec;
+  }
+
+  const QString sudo = QStandardPaths::findExecutable(QStringLiteral("sudo"));
+  if (!sudo.isEmpty()) {
+    const QProcessEnvironment env = QProcessEnvironment::systemEnvironment();
+    if (!env.value(QStringLiteral("SUDO_ASKPASS")).isEmpty()) {
+      *arguments = {QStringLiteral("-A"), QStringLiteral("/bin/sh"),
+                    QStringLiteral("-c"), command};
+      return sudo;
+    }
+
+    const QFileInfo stdinInfo(QStringLiteral("/proc/self/fd/0"));
+    const QString stdinTarget = stdinInfo.symLinkTarget();
+    if (stdinInfo.exists() &&
+        (stdinTarget.startsWith(QStringLiteral("/dev/pts/")) ||
+         stdinTarget == QStringLiteral("/dev/tty"))) {
+      *arguments = {QStringLiteral("/bin/sh"), QStringLiteral("-c"), command};
+      return sudo;
+    }
+  }
+
+  return {};
+}
+
+QString enableFuseIoUring()
+{
+  QStringList arguments;
+  const QString helper = findPrivilegeHelper(&arguments);
+  if (helper.isEmpty()) {
+    return QObject::tr("Install pkexec/polkit, or configure sudo askpass, then try "
+                       "again.");
+  }
+
+  QProcess process;
+  process.start(helper, arguments);
+  if (!process.waitForStarted(5000)) {
+    return QObject::tr("Failed to start %1.").arg(helper);
+  }
+
+  if (!process.waitForFinished(120000)) {
+    process.kill();
+    process.waitForFinished(3000);
+    return QObject::tr("Timed out waiting for administrator authentication.");
+  }
+
+  if (process.exitStatus() != QProcess::NormalExit || process.exitCode() != 0) {
+    const QString stderrText = QString::fromLocal8Bit(process.readAllStandardError())
+                                   .trimmed();
+    if (!stderrText.isEmpty()) {
+      return stderrText;
+    }
+    return QObject::tr("Administrator authentication was cancelled or failed.");
+  }
+
+  if (readFuseIoUringState() != FuseIoUringState::Enabled) {
+    return QObject::tr("The kernel did not accept the FUSE io_uring setting.");
+  }
+
+  return {};
+}
 }
 
 ProtonSettingsTab::ProtonSettingsTab(Settings& s, SettingsDialog& d)
@@ -97,6 +203,8 @@ ProtonSettingsTab::ProtonSettingsTab(Settings& s, SettingsDialog& d)
                    &ProtonSettingsTab::onBrowsePrefixLocation);
   QObject::connect(ui->downloadSLRButton, &QPushButton::clicked, this,
                    &ProtonSettingsTab::onDownloadSLR);
+  QObject::connect(ui->fuseIoUringCheckBox, &QCheckBox::clicked, this,
+                   &ProtonSettingsTab::onFuseIoUringToggled);
 
   QObject::connect(&m_installWatcher, &QFutureWatcher<InstallResult>::finished, this,
                    &ProtonSettingsTab::onInstallFinished);
@@ -183,6 +291,8 @@ void ProtonSettingsTab::refreshState()
   ui->openPrefixFolderButton->setEnabled(!m_busy && active);
   ui->winetricksButton->setEnabled(!m_busy && active);
   ui->protonVersionCombo->setEnabled(!m_busy);
+
+  refreshFuseIoUringState();
 }
 
 void ProtonSettingsTab::setBusy(bool busy)
@@ -332,6 +442,74 @@ void ProtonSettingsTab::onDownloadSLR()
   progress->show();
 }
 
+void ProtonSettingsTab::refreshFuseIoUringState()
+{
+  QSignalBlocker blocker(ui->fuseIoUringCheckBox);
+  Q_UNUSED(blocker);
+
+  const FuseIoUringState state = readFuseIoUringState();
+  ui->fuseIoUringCheckBox->setVisible(true);
+
+  switch (state) {
+  case FuseIoUringState::Enabled:
+    ui->fuseIoUringCheckBox->setChecked(true);
+    ui->fuseIoUringCheckBox->setEnabled(false);
+    ui->fuseIoUringCheckBox->setToolTip(
+        tr("FUSE io_uring is enabled in the kernel. It applies to new VFS "
+           "mounts after relaunch/remount."));
+    break;
+  case FuseIoUringState::Disabled:
+    ui->fuseIoUringCheckBox->setChecked(false);
+    ui->fuseIoUringCheckBox->setEnabled(!m_busy);
+    ui->fuseIoUringCheckBox->setToolTip(
+        tr("Enable the kernel FUSE io_uring transport for new VFS mounts. "
+           "Requires administrator authentication and a VFS remount; Fluorine "
+           "falls back automatically when unsupported."));
+    break;
+  case FuseIoUringState::Unsupported:
+    ui->fuseIoUringCheckBox->setChecked(false);
+    ui->fuseIoUringCheckBox->setEnabled(false);
+    ui->fuseIoUringCheckBox->setToolTip(
+        tr("This kernel does not expose %1. FUSE io_uring requires kernel "
+           "support for CONFIG_FUSE_IO_URING.")
+            .arg(QString::fromUtf8(kFuseIoUringParameter)));
+    break;
+  case FuseIoUringState::Unknown:
+    ui->fuseIoUringCheckBox->setChecked(false);
+    ui->fuseIoUringCheckBox->setEnabled(!m_busy);
+    ui->fuseIoUringCheckBox->setToolTip(
+        tr("Fluorine could not read the kernel FUSE io_uring setting. Click "
+           "to try enabling it with administrator authentication."));
+    break;
+  }
+}
+
+void ProtonSettingsTab::onFuseIoUringToggled(bool checked)
+{
+  if (!checked) {
+    refreshFuseIoUringState();
+    return;
+  }
+
+  MOBase::log::info("[VFS] user requested enabling FUSE io_uring via settings UI");
+
+  const QString error = enableFuseIoUring();
+  if (!error.isEmpty()) {
+    MOBase::log::warn("[VFS] failed to enable FUSE io_uring: {}", error);
+    QMessageBox::warning(parentWidget(), tr("FUSE io_uring"),
+                         tr("Could not enable FUSE io_uring:\n%1").arg(error));
+    refreshFuseIoUringState();
+    return;
+  }
+
+  MOBase::log::info("[VFS] kernel FUSE io_uring parameter is now enabled");
+  QMessageBox::information(
+      parentWidget(), tr("FUSE io_uring"),
+      tr("FUSE io_uring is enabled. Restart the game/VFS mount before testing; "
+         "existing mounts keep their current transport."));
+  refreshFuseIoUringState();
+}
+
 void ProtonSettingsTab::onBrowsePrefixLocation()
 {
   const QString dir = QFileDialog::getExistingDirectory(
@@ -560,4 +738,3 @@ void ProtonSettingsTab::onInstallFinished()
   ui->protonStatusLabel->setText(tr("Done"));
   refreshState();
 }
-
diff --git a/src/src/settingsdialogproton.h b/src/src/settingsdialogproton.h
index 5eee3bd..321e5a2 100644
--- a/src/src/settingsdialogproton.h
+++ b/src/src/settingsdialogproton.h
@@ -33,9 +33,11 @@ private:
   void onWinetricks();
   void onBrowsePrefixLocation();
   void onDownloadSLR();
+  void onFuseIoUringToggled(bool checked);
 
   static QString ensureWinetricks();
   static QString findProtonWine(const QString& protonPath);
+  void refreshFuseIoUringState();
 
   void runPrefixSetupDialog(uint32_t appId, const QString& prefixPath,
                             const QString& protonName, const QString& protonPath);