git: 4a0db5e2920c - main - evdev: Extend EVIOCGRAB ioctl scope to cover sysmouse interface

The branch main has been updated by wulf:

URL: https://cgit.FreeBSD.org/src/commit/?id=4a0db5e2920c0e0df52d6888bdd732df95706dfc

commit 4a0db5e2920c0e0df52d6888bdd732df95706dfc
Author:     Vladimir Kondratyev <wulf@FreeBSD.org>
AuthorDate: 2022-11-17 21:48:42 +0000
Commit:     Vladimir Kondratyev <wulf@FreeBSD.org>
CommitDate: 2022-11-17 21:48:42 +0000

    evdev: Extend EVIOCGRAB ioctl scope to cover sysmouse interface
    
    of psm(4), ums(4) and sysmouse(4) drivers.
    EVIOCGRAB ioctl execution on /dev/input/event# device node gains
    exclusive access to this device to caller. It is used mostly for
    development purposes and remote control software. See e.g.
    https://reviews.freebsd.org/D30020 which is the reason of creation
    of this change.
    
    MFC after:      2 weeks
    Tested by:      corvink
    Differential revision:  https://reviews.freebsd.org/D30542
---
 sys/dev/atkbdc/psm.c       | 12 ++++++++----
 sys/dev/evdev/evdev.c      | 11 +++++++++++
 sys/dev/evdev/evdev.h      |  1 +
 sys/dev/syscons/sysmouse.c |  2 ++
 sys/dev/usb/input/ums.c    |  4 ++++
 sys/dev/vt/vt_sysmouse.c   |  2 ++
 6 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/sys/dev/atkbdc/psm.c b/sys/dev/atkbdc/psm.c
index b3e036ebc134..97bf1b859dd2 100644
--- a/sys/dev/atkbdc/psm.c
+++ b/sys/dev/atkbdc/psm.c
@@ -5111,6 +5111,10 @@ psmsoftintr(void *arg)
 			break;
 		}
 
+	/* Store last packet for reinjection if it has not been set already */
+	if (timevalisset(&sc->idletimeout) && sc->idlepacket.inputbytes == 0)
+		sc->idlepacket = *pb;
+
 #ifdef EVDEV_SUPPORT
 	if (evdev_rcpt_mask & EVDEV_RCPT_HW_MOUSE &&
 	    sc->hw.model != MOUSE_MODEL_ELANTECH &&
@@ -5144,6 +5148,10 @@ psmsoftintr(void *arg)
 		evdev_push_mouse_btn(sc->evdev_r, ms.button);
 		evdev_sync(sc->evdev_r);
 	}
+
+	if ((sc->evdev_a != NULL && evdev_is_grabbed(sc->evdev_a)) ||
+	    (sc->evdev_r != NULL && evdev_is_grabbed(sc->evdev_r)))
+		goto next;
 #endif
 
 	/* scale values */
@@ -5164,10 +5172,6 @@ psmsoftintr(void *arg)
 		}
 	}
 
-	/* Store last packet for reinjection if it has not been set already */
-	if (timevalisset(&sc->idletimeout) && sc->idlepacket.inputbytes == 0)
-		sc->idlepacket = *pb;
-
 	ms.dx = x;
 	ms.dy = y;
 	ms.dz = z;
diff --git a/sys/dev/evdev/evdev.c b/sys/dev/evdev/evdev.c
index 2fd7c2e201ea..a0a039f0b691 100644
--- a/sys/dev/evdev/evdev.c
+++ b/sys/dev/evdev/evdev.c
@@ -1094,6 +1094,17 @@ evdev_release_client(struct evdev_dev *evdev, struct evdev_client *client)
 	return (0);
 }
 
+bool
+evdev_is_grabbed(struct evdev_dev *evdev)
+{
+	/*
+	 * The function is intended to be called from evdev-unrelated parts of
+	 * code like syscons-compatible parts of mouse and keyboard drivers.
+	 * That makes unlocked read-only access acceptable.
+	 */
+	return (evdev->ev_grabber != NULL);
+}
+
 static void
 evdev_repeat_callout(void *arg)
 {
diff --git a/sys/dev/evdev/evdev.h b/sys/dev/evdev/evdev.h
index 90bea09b70c9..892e6b1bc071 100644
--- a/sys/dev/evdev/evdev.h
+++ b/sys/dev/evdev/evdev.h
@@ -154,6 +154,7 @@ void evdev_set_repeat_params(struct evdev_dev *, uint16_t, int);
 int evdev_set_report_size(struct evdev_dev *, size_t);
 void evdev_set_flag(struct evdev_dev *, uint16_t);
 void *evdev_get_softc(struct evdev_dev *);
+bool evdev_is_grabbed(struct evdev_dev *);
 
 /* Multitouch related functions: */
 int evdev_mt_id_to_slot(struct evdev_dev *, int32_t);
diff --git a/sys/dev/syscons/sysmouse.c b/sys/dev/syscons/sysmouse.c
index ef851058a6ef..73167bdb34f8 100644
--- a/sys/dev/syscons/sysmouse.c
+++ b/sys/dev/syscons/sysmouse.c
@@ -295,6 +295,8 @@ sysmouse_event(mouse_info_t *info)
 
 #ifdef EVDEV_SUPPORT
 	smdev_evdev_write(x, y, z, mouse_status.button);
+	if (evdev_is_grabbed(sysmouse_evdev))
+		goto done;
 #endif
 
 	if (!tty_opened(sysmouse_tty))
diff --git a/sys/dev/usb/input/ums.c b/sys/dev/usb/input/ums.c
index 5b3ac2af4cd0..987c4b9d1309 100644
--- a/sys/dev/usb/input/ums.c
+++ b/sys/dev/usb/input/ums.c
@@ -875,6 +875,10 @@ ums_put_queue(struct ums_softc *sc, int32_t dx, int32_t dy,
 {
 	uint8_t buf[8];
 
+#ifdef EVDEV_SUPPORT
+	if (evdev_is_grabbed(sc->sc_evdev))
+		return;
+#endif
 	if (1) {
 		if (dx > 254)
 			dx = 254;
diff --git a/sys/dev/vt/vt_sysmouse.c b/sys/dev/vt/vt_sysmouse.c
index e10ac829abf3..c6426f3a8f17 100644
--- a/sys/dev/vt/vt_sysmouse.c
+++ b/sys/dev/vt/vt_sysmouse.c
@@ -249,6 +249,8 @@ sysmouse_process_event(mouse_info_t *mi)
 
 #ifdef EVDEV_SUPPORT
 	sysmouse_evdev_store(x, y, z, sysmouse_status.button);
+	if (evdev_is_grabbed(sysmouse_evdev))
+		goto done;
 #endif
 
 	/* The first five bytes are compatible with MouseSystems. */