drm/xe: Runtime PM wake on every IOCTL

Let's ensure our PCI device is awaken on every IOCTL entry.
Let's increase the runtime_pm protection and start moving
that to the outer bounds.

v2: minor typo fix and renaming function to make it clear
    that is intended to be used by ioctl only. (Matt)
v3: Make it NULL if CONFIG_COMPAT is not selected.

Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Francois Dugast <francois.dugast@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240222163937.138342-3-rodrigo.vivi@intel.com

drivers/gpu/drm/xe/xe_device.c

@@ -136,15 +136,48 @@ static const struct drm_ioctl_desc xe_ioctls[] = {
 			  DRM_RENDER_ALLOW),
 };
 
+static long xe_drm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct drm_file *file_priv = file->private_data;
+	struct xe_device *xe = to_xe_device(file_priv->minor->dev);
+	long ret;
+
+	ret = xe_pm_runtime_get_ioctl(xe);
+	if (ret >= 0)
+		ret = drm_ioctl(file, cmd, arg);
+	xe_pm_runtime_put(xe);
+
+	return ret;
+}
+
+#ifdef CONFIG_COMPAT
+static long xe_drm_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct drm_file *file_priv = file->private_data;
+	struct xe_device *xe = to_xe_device(file_priv->minor->dev);
+	long ret;
+
+	ret = xe_pm_runtime_get_ioctl(xe);
+	if (ret >= 0)
+		ret = drm_compat_ioctl(file, cmd, arg);
+	xe_pm_runtime_put(xe);
+
+	return ret;
+}
+#else
+/* similarly to drm_compat_ioctl, let's it be assigned to .compat_ioct unconditionally */
+#define xe_drm_compat_ioctl NULL
+#endif
+
 static const struct file_operations xe_driver_fops = {
 	.owner = THIS_MODULE,
 	.open = drm_open,
 	.release = drm_release_noglobal,
-	.unlocked_ioctl = drm_ioctl,
+	.unlocked_ioctl = xe_drm_ioctl,
 	.mmap = drm_gem_mmap,
 	.poll = drm_poll,
 	.read = drm_read,
-	.compat_ioctl = drm_compat_ioctl,
+	.compat_ioctl = xe_drm_compat_ioctl,
 	.llseek = noop_llseek,
 #ifdef CONFIG_PROC_FS
 	.show_fdinfo = drm_show_fdinfo,

drivers/gpu/drm/xe/xe_pm.c

@@ -430,6 +430,21 @@ int xe_pm_runtime_put(struct xe_device *xe)
 	return pm_runtime_put(xe->drm.dev);
 }
 
+/**
+ * xe_pm_runtime_get_ioctl - Get a runtime_pm reference before ioctl
+ * @xe: xe device instance
+ *
+ * Returns: Any number greater than or equal to 0 for success, negative error
+ * code otherwise.
+ */
+int xe_pm_runtime_get_ioctl(struct xe_device *xe)
+{
+	if (WARN_ON(xe_pm_read_callback_task(xe) == current))
+		return -ELOOP;
+
+	return pm_runtime_get_sync(xe->drm.dev);
+}
+
 /**
  * xe_pm_runtime_get_if_active - Get a runtime_pm reference if device active
  * @xe: xe device instance

drivers/gpu/drm/xe/xe_pm.h

@@ -27,6 +27,7 @@ bool xe_pm_runtime_suspended(struct xe_device *xe);
 int xe_pm_runtime_suspend(struct xe_device *xe);
 int xe_pm_runtime_resume(struct xe_device *xe);
 int xe_pm_runtime_get(struct xe_device *xe);
+int xe_pm_runtime_get_ioctl(struct xe_device *xe);
 int xe_pm_runtime_put(struct xe_device *xe);
 int xe_pm_runtime_get_if_active(struct xe_device *xe);
 void xe_pm_assert_unbounded_bridge(struct xe_device *xe);