[PATCH v3 05/12] drm/fbdev: Store fbdev module parameters in separate file

Thomas Zimmermann tzimmermann at suse.de
Tue Oct 8 11:59:24 UTC 2024


The fbdev code does not really belong into drm_kms_helper.ko. But
there are module parameters that control the behavior of the fbdev
emulation. It is not possible to remove them from the module without
breaking someone's installation.

Therefore move the fbdev module parameters to drm_kms_helper_common.c,
so that the actual fbdev implementaton can later go into a separate
module.

Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
---
 drivers/gpu/drm/drm_fb_helper.c         | 31 ----------------------
 drivers/gpu/drm/drm_internal.h          |  7 +++++
 drivers/gpu/drm/drm_kms_helper_common.c | 35 +++++++++++++++++++++++++
 3 files changed, 42 insertions(+), 31 deletions(-)

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index d5e8994345bb..004f7c437897 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -46,37 +46,6 @@
 #include "drm_internal.h"
 #include "drm_crtc_internal.h"
 
-static bool drm_fbdev_emulation = true;
-module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600);
-MODULE_PARM_DESC(fbdev_emulation,
-		 "Enable legacy fbdev emulation [default=true]");
-
-static int drm_fbdev_overalloc = CONFIG_DRM_FBDEV_OVERALLOC;
-module_param(drm_fbdev_overalloc, int, 0444);
-MODULE_PARM_DESC(drm_fbdev_overalloc,
-		 "Overallocation of the fbdev buffer (%) [default="
-		 __MODULE_STRING(CONFIG_DRM_FBDEV_OVERALLOC) "]");
-
-/*
- * In order to keep user-space compatibility, we want in certain use-cases
- * to keep leaking the fbdev physical address to the user-space program
- * handling the fbdev buffer.
- *
- * This is a bad habit, essentially kept to support closed-source OpenGL
- * drivers that should really be moved into open-source upstream projects
- * instead of using legacy physical addresses in user space to communicate
- * with other out-of-tree kernel modules.
- *
- * This module_param *should* be removed as soon as possible and be
- * considered as a broken and legacy behaviour from a modern fbdev device.
- */
-static bool drm_leak_fbdev_smem;
-#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
-module_param_unsafe(drm_leak_fbdev_smem, bool, 0600);
-MODULE_PARM_DESC(drm_leak_fbdev_smem,
-		 "Allow unsafe leaking fbdev physical smem address [default=false]");
-#endif
-
 static LIST_HEAD(kernel_fb_helper_list);
 static DEFINE_MUTEX(kernel_fb_helper_lock);
 
diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h
index 1705bfc90b1e..9af72bab86d1 100644
--- a/drivers/gpu/drm/drm_internal.h
+++ b/drivers/gpu/drm/drm_internal.h
@@ -54,6 +54,13 @@ bool drm_dev_needs_global_mutex(struct drm_device *dev);
 struct drm_file *drm_file_alloc(struct drm_minor *minor);
 void drm_file_free(struct drm_file *file);
 
+/* drm_kms_helper_common.c */
+#if defined(CONFIG_DRM_FBDEV_EMULATION)
+extern bool drm_fbdev_emulation;
+extern int drm_fbdev_overalloc;
+extern bool drm_leak_fbdev_smem;
+#endif
+
 #ifdef CONFIG_PCI
 
 /* drm_pci.c */
diff --git a/drivers/gpu/drm/drm_kms_helper_common.c b/drivers/gpu/drm/drm_kms_helper_common.c
index 0c7550c0462b..cfdbc1ac88dc 100644
--- a/drivers/gpu/drm/drm_kms_helper_common.c
+++ b/drivers/gpu/drm/drm_kms_helper_common.c
@@ -27,6 +27,41 @@
 
 #include <linux/module.h>
 
+#include "drm_internal.h"
+
+#if defined(CONFIG_DRM_FBDEV_EMULATION)
+bool drm_fbdev_emulation = true;
+module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600);
+MODULE_PARM_DESC(fbdev_emulation,
+		 "Enable legacy fbdev emulation [default=true]");
+
+int drm_fbdev_overalloc = CONFIG_DRM_FBDEV_OVERALLOC;
+module_param(drm_fbdev_overalloc, int, 0444);
+MODULE_PARM_DESC(drm_fbdev_overalloc,
+		 "Overallocation of the fbdev buffer (%) [default="
+		 __MODULE_STRING(CONFIG_DRM_FBDEV_OVERALLOC) "]");
+
+/*
+ * In order to keep user-space compatibility, we want in certain use-cases
+ * to keep leaking the fbdev physical address to the user-space program
+ * handling the fbdev buffer.
+ *
+ * This is a bad habit, essentially kept to support closed-source OpenGL
+ * drivers that should really be moved into open-source upstream projects
+ * instead of using legacy physical addresses in user space to communicate
+ * with other out-of-tree kernel modules.
+ *
+ * This module_param *should* be removed as soon as possible and be
+ * considered as a broken and legacy behaviour from a modern fbdev device.
+ */
+bool drm_leak_fbdev_smem;
+#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
+module_param_unsafe(drm_leak_fbdev_smem, bool, 0600);
+MODULE_PARM_DESC(drm_leak_fbdev_smem,
+		 "Allow unsafe leaking fbdev physical smem address [default=false]");
+#endif
+#endif
+
 MODULE_AUTHOR("David Airlie, Jesse Barnes");
 MODULE_DESCRIPTION("DRM KMS helper");
 MODULE_LICENSE("GPL and additional rights");
-- 
2.46.0



More information about the dri-devel mailing list