vt(4): Save/restore keyboard mode & LED states when switching window

(MFC of r272416)

Add new functions to manipulate these mode & state, instead of calling
kbdd_ioctl() everyhere.

This fixes at least two bugs:

    1. The state of the Scroll Lock LED and the state of scroll mode
       could be out-of-sync. For instance, if one enables scroll mode on
       window #1 and switches to window #2, the LED would remain on, but
       the window wouldn't be in scroll mode.

       Similarily, when switching between a console and an X.Org
       session, the LED states could be inconsistent with the real
       state.

    2. When exiting from an X.Org session, the user could be unable to
       type anything. The workaround was to switch to another console
       window and come back.

Differential Revision:	https://reviews.freebsd.org/D821
Reviewed by:	ray@
Approved by:	ray@
Tested by:	kwm@

2 files changed, 216 insertions, 36 deletions

diff --git a/sys/dev/vt/vt.h b/sys/dev/vt/vt.h
index 2501928..ea93bf1 100644
--- a/sys/dev/vt/vt.h
+++ b/sys/dev/vt/vt.h
@@ -261,6 +261,7 @@ struct vt_window {
 	unsigned int		 vw_number;	/* (c) Window number. */
 	int			 vw_kbdmode;	/* (?) Keyboard mode. */
 	int			 vw_prev_kbdmode;/* (?) Previous mode. */
+	int			 vw_kbdstate;	/* (?) Keyboard state. */
 	int			 vw_grabbed;	/* (?) Grab count. */
 	char			*vw_kbdsq;	/* Escape sequence queue*/
 	unsigned int		 vw_flags;	/* (d) Per-window flags. */
diff --git a/sys/dev/vt/vt_core.c b/sys/dev/vt/vt_core.c
index 4e8d19b..2dd7e3f 100644
--- a/sys/dev/vt/vt_core.c
+++ b/sys/dev/vt/vt_core.c
@@ -298,6 +298,97 @@ vt_switch_timer(void *arg)
 }
 
 static int
+vt_save_kbd_mode(struct vt_window *vw, keyboard_t *kbd)
+{
+	int mode, ret;
+
+	mode = 0;
+	ret = kbdd_ioctl(kbd, KDGKBMODE, (caddr_t)&mode);
+	if (ret == ENOIOCTL)
+		ret = ENODEV;
+	if (ret != 0)
+		return (ret);
+
+	vw->vw_kbdmode = mode;
+
+	return (0);
+}
+
+static int
+vt_update_kbd_mode(struct vt_window *vw, keyboard_t *kbd)
+{
+	int ret;
+
+	ret = kbdd_ioctl(kbd, KDSKBMODE, (caddr_t)&vw->vw_kbdmode);
+	if (ret == ENOIOCTL)
+		ret = ENODEV;
+
+	return (ret);
+}
+
+static int
+vt_save_kbd_state(struct vt_window *vw, keyboard_t *kbd)
+{
+	int state, ret;
+
+	state = 0;
+	ret = kbdd_ioctl(kbd, KDGKBSTATE, (caddr_t)&state);
+	if (ret == ENOIOCTL)
+		ret = ENODEV;
+	if (ret != 0)
+		return (ret);
+
+	vw->vw_kbdstate &= ~LOCK_MASK;
+	vw->vw_kbdstate |= state & LOCK_MASK;
+
+	return (0);
+}
+
+static int
+vt_update_kbd_state(struct vt_window *vw, keyboard_t *kbd)
+{
+	int state, ret;
+
+	state = vw->vw_kbdstate & LOCK_MASK;
+	ret = kbdd_ioctl(kbd, KDSKBSTATE, (caddr_t)&state);
+	if (ret == ENOIOCTL)
+		ret = ENODEV;
+
+	return (ret);
+}
+
+static int
+vt_save_kbd_leds(struct vt_window *vw, keyboard_t *kbd)
+{
+	int leds, ret;
+
+	leds = 0;
+	ret = kbdd_ioctl(kbd, KDGETLED, (caddr_t)&leds);
+	if (ret == ENOIOCTL)
+		ret = ENODEV;
+	if (ret != 0)
+		return (ret);
+
+	vw->vw_kbdstate &= ~LED_MASK;
+	vw->vw_kbdstate |= leds & LED_MASK;
+
+	return (0);
+}
+
+static int
+vt_update_kbd_leds(struct vt_window *vw, keyboard_t *kbd)
+{
+	int leds, ret;
+
+	leds = vw->vw_kbdstate & LED_MASK;
+	ret = kbdd_ioctl(kbd, KDSETLED, (caddr_t)&leds);
+	if (ret == ENOIOCTL)
+		ret = ENODEV;
+
+	return (ret);
+}
+
+static int
 vt_window_preswitch(struct vt_window *vw, struct vt_window *curvw)
 {
 
@@ -409,7 +500,11 @@ vt_window_switch(struct vt_window *vw)
 	mtx_lock(&Giant);
 	kbd = kbd_get_keyboard(vd->vd_keyboard);
 	if (kbd != NULL) {
-		kbdd_ioctl(kbd, KDSKBMODE, (void *)&vw->vw_kbdmode);
+		if (curvw->vw_kbdmode == K_XLATE)
+			vt_save_kbd_state(curvw, kbd);
+
+		vt_update_kbd_mode(vw, kbd);
+		vt_update_kbd_state(vw, kbd);
 	}
 	mtx_unlock(&Giant);
 	DPRINTF(10, "%s(ttyv%d) done\n", __func__, vw->vw_number);
@@ -602,7 +697,6 @@ static int
 vt_processkey(keyboard_t *kbd, struct vt_device *vd, int c)
 {
 	struct vt_window *vw = vd->vd_curwindow;
-	int state = 0;
 
 #if VT_ALT_TO_ESC_HACK
 	if (c & RELKEY) {
@@ -665,10 +759,9 @@ vt_processkey(keyboard_t *kbd, struct vt_device *vd, int c)
 				vt_proc_window_switch(vw);
 			return (0);
 		case SLK: {
-
-			kbdd_ioctl(kbd, KDGKBSTATE, (caddr_t)&state);
+			vt_save_kbd_state(vw, kbd);
 			VT_LOCK(vd);
-			if (state & SLKED) {
+			if (vw->vw_kbdstate & SLKED) {
 				/* Turn scrolling on. */
 				vw->vw_flags |= VWF_SCROLL;
 				VTBUF_SLCK_ENABLE(&vw->vw_buf);
@@ -1201,13 +1294,11 @@ vtterm_cngetc(struct terminal *tm)
 	struct vt_window *vw = tm->tm_softc;
 	struct vt_device *vd = vw->vw_device;
 	keyboard_t *kbd;
-	int state;
 	u_int c;
 
 	if (vw->vw_kbdsq && *vw->vw_kbdsq)
 		return (*vw->vw_kbdsq++);
 
-	state = 0;
 	/* Make sure the splash screen is not there. */
 	if (vd->vd_flags & VDF_SPLASH) {
 		/* Remove splash */
@@ -1223,8 +1314,8 @@ vtterm_cngetc(struct terminal *tm)
 		return (-1);
 
 	/* Force keyboard input mode to K_XLATE */
-	c = K_XLATE;
-	kbdd_ioctl(kbd, KDSKBMODE, (void *)&c);
+	vw->vw_kbdmode = K_XLATE;
+	vt_update_kbd_mode(vw, kbd);
 
 	/* Switch the keyboard to polling to make it work here. */
 	kbdd_poll(kbd, TRUE);
@@ -1243,8 +1334,8 @@ vtterm_cngetc(struct terminal *tm)
 	if (c & SPCLKEY) {
 		switch (c) {
 		case SPCLKEY | SLK:
-			kbdd_ioctl(kbd, KDGKBSTATE, (caddr_t)&state);
-			if (state & SLKED) {
+			vt_save_kbd_state(vw, kbd);
+			if (vw->vw_kbdstate & SLKED) {
 				/* Turn scrolling on. */
 				vw->vw_flags |= VWF_SCROLL;
 				VTBUF_SLCK_ENABLE(&vw->vw_buf);
@@ -1311,7 +1402,7 @@ vtterm_cngrab(struct terminal *tm)
 	/* We shall always use the keyboard in the XLATE mode here. */
 	vw->vw_prev_kbdmode = vw->vw_kbdmode;
 	vw->vw_kbdmode = K_XLATE;
-	(void)kbdd_ioctl(kbd, KDSKBMODE, (caddr_t)&vw->vw_kbdmode);
+	vt_update_kbd_mode(vw, kbd);
 
 	kbdd_poll(kbd, TRUE);
 }
@@ -1336,7 +1427,7 @@ vtterm_cnungrab(struct terminal *tm)
 	kbdd_poll(kbd, FALSE);
 
 	vw->vw_kbdmode = vw->vw_prev_kbdmode;
-	(void)kbdd_ioctl(kbd, KDSKBMODE, (caddr_t)&vw->vw_kbdmode);
+	vt_update_kbd_mode(vw, kbd);
 	kbdd_disable(kbd);
 }
 
@@ -1890,12 +1981,8 @@ skip_thunk:
 	case SETFKEY:
 	case KDGKBINFO:
 	case KDGKBTYPE:
-	case KDSKBSTATE:	/* set keyboard state (locks) */
-	case KDGKBSTATE:	/* get keyboard state (locks) */
 	case KDGETREPEAT:	/* get keyboard repeat & delay rates */
 	case KDSETREPEAT:	/* set keyboard repeat & delay rates (new) */
-	case KDSETLED:		/* set keyboard LED status */
-	case KDGETLED:		/* get keyboard LED status */
 	case KBADDKBD:		/* add/remove keyboard to/from mux */
 	case KBRELKBD: {
 		error = 0;
@@ -1915,18 +2002,101 @@ skip_thunk:
 		}
 		return (error);
 	}
+	case KDGKBSTATE: {	/* get keyboard state (locks) */
+		error = 0;
+
+		if (vw == vd->vd_curwindow) {
+			mtx_lock(&Giant);
+			kbd = kbd_get_keyboard(vd->vd_keyboard);
+			if (kbd != NULL)
+				error = vt_save_kbd_state(vw, kbd);
+			mtx_unlock(&Giant);
+
+			if (error != 0)
+				return (error);
+		}
+
+		*(int *)data = vw->vw_kbdstate & LOCK_MASK;
+
+		return (error);
+	}
+	case KDSKBSTATE: {	/* set keyboard state (locks) */
+		int state;
+
+		state = *(int *)data;
+		if (state & ~LOCK_MASK)
+			return (EINVAL);
+
+		vw->vw_kbdstate &= ~LOCK_MASK;
+		vw->vw_kbdstate |= state;
+
+		error = 0;
+		if (vw == vd->vd_curwindow) {
+			mtx_lock(&Giant);
+			kbd = kbd_get_keyboard(vd->vd_keyboard);
+			if (kbd != NULL)
+				error = vt_update_kbd_state(vw, kbd);
+			mtx_unlock(&Giant);
+		}
+
+		return (error);
+	}
+	case KDGETLED: {	/* get keyboard LED status */
+		error = 0;
+
+		if (vw == vd->vd_curwindow) {
+			mtx_lock(&Giant);
+			kbd = kbd_get_keyboard(vd->vd_keyboard);
+			if (kbd != NULL)
+				error = vt_save_kbd_leds(vw, kbd);
+			mtx_unlock(&Giant);
+
+			if (error != 0)
+				return (error);
+		}
+
+		*(int *)data = vw->vw_kbdstate & LED_MASK;
+
+		return (error);
+	}
+	case KDSETLED: {	/* set keyboard LED status */
+		int leds;
+
+		leds = *(int *)data;
+		if (leds & ~LED_MASK)
+			return (EINVAL);
+
+		vw->vw_kbdstate &= ~LED_MASK;
+		vw->vw_kbdstate |= leds;
+
+		error = 0;
+		if (vw == vd->vd_curwindow) {
+			mtx_lock(&Giant);
+			kbd = kbd_get_keyboard(vd->vd_keyboard);
+			if (kbd != NULL)
+				error = vt_update_kbd_leds(vw, kbd);
+			mtx_unlock(&Giant);
+		}
+
+		return (error);
+	}
 	case KDGKBMODE: {
-		int mode = -1;
+		error = 0;
 
-		mtx_lock(&Giant);
-		kbd = kbd_get_keyboard(vd->vd_keyboard);
-		if (kbd != NULL) {
-			kbdd_ioctl(kbd, KDGKBMODE, (void *)&mode);
+		if (vw == vd->vd_curwindow) {
+			mtx_lock(&Giant);
+			kbd = kbd_get_keyboard(vd->vd_keyboard);
+			if (kbd != NULL)
+				error = vt_save_kbd_mode(vw, kbd);
+			mtx_unlock(&Giant);
+
+			if (error != 0)
+				return (error);
 		}
-		mtx_unlock(&Giant);
-		DPRINTF(20, "mode %d, vw_kbdmode %d\n", mode, vw->vw_kbdmode);
-		*(int *)data = mode;
-		return (0);
+
+		*(int *)data = vw->vw_kbdmode;
+
+		return (error);
 	}
 	case KDSKBMODE: {
 		int mode;
@@ -1937,19 +2107,17 @@ skip_thunk:
 		case K_RAW:
 		case K_CODE:
 			vw->vw_kbdmode = mode;
-			if (vw == vd->vd_curwindow) {
-				keyboard_t *kbd;
-				error = 0;
 
+			error = 0;
+			if (vw == vd->vd_curwindow) {
 				mtx_lock(&Giant);
 				kbd = kbd_get_keyboard(vd->vd_keyboard);
-				if (kbd != NULL) {
-					error = kbdd_ioctl(kbd, KDSKBMODE,
-					    (void *)&mode);
-				}
+				if (kbd != NULL)
+					error = vt_update_kbd_mode(vw, kbd);
 				mtx_unlock(&Giant);
 			}
-			return (0);
+
+			return (error);
 		default:
 			return (EINVAL);
 		}
@@ -1977,8 +2145,17 @@ skip_thunk:
 		return (0);
 	case CONS_GETINFO: {
 		vid_info_t *vi = (vid_info_t *)data;
+		if (vi->size != sizeof(struct vid_info))
+			return (EINVAL);
+
+		if (vw == vd->vd_curwindow) {
+			kbd = kbd_get_keyboard(vd->vd_keyboard);
+			if (kbd != NULL)
+				vt_save_kbd_state(vw, kbd);
+		}
 
 		vi->m_num = vd->vd_curwindow->vw_number + 1;
+		vi->mk_keylock = vw->vw_kbdstate & LOCK_MASK;
 		/* XXX: other fields! */
 		return (0);
 	}
@@ -2093,13 +2270,14 @@ skip_thunk:
 			    (void *)vd, vt_kbdevent, vd);
 			if (i >= 0) {
 				if (vd->vd_keyboard != -1) {
+					vt_save_kbd_state(vd->vd_curwindow, kbd);
 					kbd_release(kbd, (void *)vd);
 				}
 				kbd = kbd_get_keyboard(i);
 				vd->vd_keyboard = i;
 
-				(void)kbdd_ioctl(kbd, KDSKBMODE,
-				    (caddr_t)&vd->vd_curwindow->vw_kbdmode);
+				vt_update_kbd_mode(vd->vd_curwindow, kbd);
+				vt_update_kbd_state(vd->vd_curwindow, kbd);
 			} else {
 				error = EPERM;	/* XXX */
 			}
@@ -2115,6 +2293,7 @@ skip_thunk:
 				mtx_unlock(&Giant);
 				return (EINVAL);
 			}
+			vt_save_kbd_state(vd->vd_curwindow, kbd);
 			error = kbd_release(kbd, (void *)vd);
 			if (error == 0) {
 				vd->vd_keyboard = -1;