Merge branch 'perm-fix' into omap-for-v4.19/fixes-v2

1 files changed, 102 insertions, 21 deletions

diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index c910e74d46ff..75ebbbf0a1fb 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -129,6 +129,12 @@ static inline void fbcon_map_override(void)
 }
 #endif /* CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY */
 
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER
+static bool deferred_takeover = true;
+#else
+#define deferred_takeover false
+#endif
+
 /* font data */
 static char fontname[40];
 
@@ -499,6 +505,12 @@ static int __init fb_console_setup(char *this_opt)
 				margin_color = simple_strtoul(options, &options, 0);
 			continue;
 		}
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER
+		if (!strcmp(options, "nodefer")) {
+			deferred_takeover = false;
+			continue;
+		}
+#endif
 	}
 	return 1;
 }
@@ -828,6 +840,8 @@ static int set_con2fb_map(int unit, int newidx, int user)
 	struct fb_info *oldinfo = NULL;
  	int found, err = 0;
 
+	WARN_CONSOLE_UNLOCKED();
+
 	if (oldidx == newidx)
 		return 0;
 
@@ -2220,8 +2234,8 @@ static int fbcon_switch(struct vc_data *vc)
 	 *
 	 * info->currcon = vc->vc_num;
 	 */
-	for (i = 0; i < FB_MAX; i++) {
-		if (registered_fb[i] != NULL && registered_fb[i]->fbcon_par) {
+	for_each_registered_fb(i) {
+		if (registered_fb[i]->fbcon_par) {
 			struct fbcon_ops *o = registered_fb[i]->fbcon_par;
 
 			o->currcon = vc->vc_num;
@@ -3044,6 +3058,8 @@ static int fbcon_fb_unbind(int idx)
 {
 	int i, new_idx = -1, ret = 0;
 
+	WARN_CONSOLE_UNLOCKED();
+
 	if (!fbcon_has_console_bind)
 		return 0;
 
@@ -3094,6 +3110,11 @@ static int fbcon_fb_unregistered(struct fb_info *info)
 {
 	int i, idx;
 
+	WARN_CONSOLE_UNLOCKED();
+
+	if (deferred_takeover)
+		return 0;
+
 	idx = info->node;
 	for (i = first_fb_vc; i <= last_fb_vc; i++) {
 		if (con2fb_map[i] == idx)
@@ -3103,11 +3124,9 @@ static int fbcon_fb_unregistered(struct fb_info *info)
 	if (idx == info_idx) {
 		info_idx = -1;
 
-		for (i = 0; i < FB_MAX; i++) {
-			if (registered_fb[i] != NULL) {
-				info_idx = i;
-				break;
-			}
+		for_each_registered_fb(i) {
+			info_idx = i;
+			break;
 		}
 	}
 
@@ -3131,6 +3150,16 @@ static int fbcon_fb_unregistered(struct fb_info *info)
 static void fbcon_remap_all(int idx)
 {
 	int i;
+
+	WARN_CONSOLE_UNLOCKED();
+
+	if (deferred_takeover) {
+		for (i = first_fb_vc; i <= last_fb_vc; i++)
+			con2fb_map_boot[i] = idx;
+		fbcon_map_override();
+		return;
+	}
+
 	for (i = first_fb_vc; i <= last_fb_vc; i++)
 		set_con2fb_map(i, idx, 0);
 
@@ -3177,9 +3206,16 @@ static int fbcon_fb_registered(struct fb_info *info)
 {
 	int ret = 0, i, idx;
 
+	WARN_CONSOLE_UNLOCKED();
+
 	idx = info->node;
 	fbcon_select_primary(info);
 
+	if (deferred_takeover) {
+		pr_info("fbcon: Deferring console take-over\n");
+		return 0;
+	}
+
 	if (info_idx == -1) {
 		for (i = first_fb_vc; i <= last_fb_vc; i++) {
 			if (con2fb_map_boot[i] == idx) {
@@ -3555,23 +3591,64 @@ static int fbcon_init_device(void)
 	return 0;
 }
 
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER
+static void fbcon_register_existing_fbs(struct work_struct *work)
+{
+	int i;
+
+	console_lock();
+
+	for_each_registered_fb(i)
+		fbcon_fb_registered(registered_fb[i]);
+
+	console_unlock();
+}
+
+static struct notifier_block fbcon_output_nb;
+static DECLARE_WORK(fbcon_deferred_takeover_work, fbcon_register_existing_fbs);
+
+static int fbcon_output_notifier(struct notifier_block *nb,
+				 unsigned long action, void *data)
+{
+	WARN_CONSOLE_UNLOCKED();
+
+	pr_info("fbcon: Taking over console\n");
+
+	dummycon_unregister_output_notifier(&fbcon_output_nb);
+	deferred_takeover = false;
+	logo_shown = FBCON_LOGO_DONTSHOW;
+
+	/* We may get called in atomic context */
+	schedule_work(&fbcon_deferred_takeover_work);
+
+	return NOTIFY_OK;
+}
+#endif
+
 static void fbcon_start(void)
 {
+	WARN_CONSOLE_UNLOCKED();
+
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER
+	if (conswitchp != &dummy_con)
+		deferred_takeover = false;
+
+	if (deferred_takeover) {
+		fbcon_output_nb.notifier_call = fbcon_output_notifier;
+		dummycon_register_output_notifier(&fbcon_output_nb);
+		return;
+	}
+#endif
+
 	if (num_registered_fb) {
 		int i;
 
-		console_lock();
-
-		for (i = 0; i < FB_MAX; i++) {
-			if (registered_fb[i] != NULL) {
-				info_idx = i;
-				break;
-			}
+		for_each_registered_fb(i) {
+			info_idx = i;
+			break;
 		}
 
 		do_fbcon_takeover(0);
-		console_unlock();
-
 	}
 }
 
@@ -3583,18 +3660,22 @@ static void fbcon_exit(void)
 	if (fbcon_has_exited)
 		return;
 
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER
+	if (deferred_takeover) {
+		dummycon_unregister_output_notifier(&fbcon_output_nb);
+		deferred_takeover = false;
+	}
+#endif
+
 	kfree((void *)softback_buf);
 	softback_buf = 0UL;
 
-	for (i = 0; i < FB_MAX; i++) {
+	for_each_registered_fb(i) {
 		int pending = 0;
 
 		mapped = 0;
 		info = registered_fb[i];
 
-		if (info == NULL)
-			continue;
-
 		if (info->queue.func)
 			pending = cancel_work_sync(&info->queue);
 		DPRINTK("fbcon: %s pending work\n", (pending ? "canceled" :
@@ -3650,8 +3731,8 @@ void __init fb_console_init(void)
 	for (i = 0; i < MAX_NR_CONSOLES; i++)
 		con2fb_map[i] = -1;
 
-	console_unlock();
 	fbcon_start();
+	console_unlock();
 }
 
 #ifdef MODULE