[RFC PATCH v3 06/13] vt: Redraw bootsplash fully on console_unblank

From: Max Staudt
Date: Wed Jan 17 2018 - 15:57:48 EST


After exiting a KD_GRAPHICS program and falling back to the text
console, a previously enabled splash needs to be fully redrawn.

This corner case was introduced with selective re-drawing while
implementing animations.

Without this patch, the following happens:

1. Switch to a text console
2. Enable splash
3. Start X (or any other KD_GRAPHICS program)
4. Exit X
5. Splash is not seen, apart from animations

Signed-off-by: Max Staudt <mstaudt@xxxxxxx>
Reviewed-by: Oliver Neukum <oneukum@xxxxxxxx>
---
drivers/tty/vt/vt.c | 2 ++
drivers/video/fbdev/core/bootsplash.c | 15 +++++++++------
include/linux/bootsplash.h | 4 ++++
3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 2ebaba16f785..416735ab6dc1 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -102,6 +102,7 @@
#include <linux/uaccess.h>
#include <linux/kdb.h>
#include <linux/ctype.h>
+#include <linux/bootsplash.h>

#define MAX_NR_CON_DRIVER 16

@@ -3903,6 +3904,7 @@ void do_unblank_screen(int leaving_gfx)
}

console_blanked = 0;
+ bootsplash_mark_dirty();
if (vc->vc_sw->con_blank(vc, 0, leaving_gfx) || vt_force_oops_output(vc))
/* Low-level driver cannot restore -> do it ourselves */
update_screen(vc);
diff --git a/drivers/video/fbdev/core/bootsplash.c b/drivers/video/fbdev/core/bootsplash.c
index c8642142cfea..13fcaabbc2ca 100644
--- a/drivers/video/fbdev/core/bootsplash.c
+++ b/drivers/video/fbdev/core/bootsplash.c
@@ -165,6 +165,13 @@ bool bootsplash_would_render_now(void)
&& bootsplash_is_enabled();
}

+void bootsplash_mark_dirty(void)
+{
+ mutex_lock(&splash_state.data_lock);
+ splash_state.splash_fb = NULL;
+ mutex_unlock(&splash_state.data_lock);
+}
+
bool bootsplash_is_enabled(void)
{
bool was_enabled;
@@ -206,9 +213,7 @@ void bootsplash_enable(void)

if (!was_enabled) {
/* Force a full redraw when the splash is re-activated */
- mutex_lock(&splash_state.data_lock);
- splash_state.splash_fb = NULL;
- mutex_unlock(&splash_state.data_lock);
+ bootsplash_mark_dirty();

schedule_work(&splash_state.work_redraw_vc);
}
@@ -272,9 +277,7 @@ static int splash_resume(struct device *device)
* Force full redraw on resume since we've probably lost the
* framebuffer's contents meanwhile
*/
- mutex_lock(&splash_state.data_lock);
- splash_state.splash_fb = NULL;
- mutex_unlock(&splash_state.data_lock);
+ bootsplash_mark_dirty();

if (bootsplash_would_render_now())
schedule_work(&splash_state.work_redraw_vc);
diff --git a/include/linux/bootsplash.h b/include/linux/bootsplash.h
index c6dd0b43180d..4075098aaadd 100644
--- a/include/linux/bootsplash.h
+++ b/include/linux/bootsplash.h
@@ -19,6 +19,8 @@ extern void bootsplash_render_full(struct fb_info *info);

extern bool bootsplash_would_render_now(void);

+extern void bootsplash_mark_dirty(void);
+
extern bool bootsplash_is_enabled(void);
extern void bootsplash_disable(void);
extern void bootsplash_enable(void);
@@ -31,6 +33,8 @@ extern void bootsplash_init(void);

#define bootsplash_would_render_now() (false)

+#define bootsplash_mark_dirty()
+
#define bootsplash_is_enabled() (false)
#define bootsplash_disable()
#define bootsplash_enable()
--
2.12.3