* Use two cdevsw's for ugen(4): one for control endpoints, and one for

  data endpoints.  The control endpoint doesn't need read/write/poll
  operations, and more importantly, the thread counts should be
  separate so that the control endpoint can properly reference itself
  while deleting and recreating the data endpoints.
* Add some macros that handle referencing/releasing devices, and use them
  for sleeping/woken-up and open/close operations as apppropriate.
* Use d_purge for FreeBSD, and a loop testing the open status for all
  the endpoints for NetBSD and OpenBSD, so that when the device is
  detached, the right thing always happens.

1 files changed, 91 insertions, 20 deletions

diff --git a/sys/dev/usb/ugen.c b/sys/dev/usb/ugen.c
index b0564d1..8e4b05a 100644
--- a/sys/dev/usb/ugen.c
+++ b/sys/dev/usb/ugen.c
@@ -144,7 +144,30 @@ struct ugen_softc {
 #define OUT 0
 #define IN  1
 
+#ifdef __FreeBSD__
+#define	UGEN_DEV_REF(dev, sc)					\
+	if ((sc)->sc_dying || dev_refthread(dev) == NULL)	\
+		return (ENXIO)
+#define	UGEN_DEV_RELE(dev, sc)	\
+	dev_relthread(dev)
+#define	UGEN_DEV_OPEN(dev, sc)		\
+	/* handled by dev layer */
+#define	UGEN_DEV_CLOSE(dev, sc)		\
+	/* handled by dev layer */
+#else
 	int sc_refcnt;
+#define	UGEN_DEV_REF(dev, sc)	\
+	if ((sc)->sc_dying)	\
+		return (ENXIO);	\
+	(sc)->sc_refcnt++
+#define	UGEN_DEV_RELE(dev, sc)				\
+	if (--(sc)->sc_refcnt < 0)			\
+		usb_detach_wakeup(USBDEV((sc)->sc_dev))
+#define	UGEN_DEV_OPEN(dev, sc)	\
+	(sc)->sc_refcnt++
+#define	UGEN_DEV_CLOSE(dev, sc)	\
+	UGEN_DEV_RELE(dev, sc)
+#endif
 	u_char sc_dying;
 };
 
@@ -157,7 +180,20 @@ d_read_t  ugenread;
 d_write_t ugenwrite;
 d_ioctl_t ugenioctl;
 d_poll_t  ugenpoll;
+d_purge_t ugenpurge;
 
+Static struct cdevsw ugenctl_cdevsw = {
+	.d_version =	D_VERSION,
+	.d_flags =	D_NEEDGIANT,
+	.d_open =	ugenopen,
+	.d_close =	ugenclose,
+	.d_ioctl =	ugenioctl,
+	.d_purge =	ugenpurge,
+	.d_name =	"ugenctl",
+#if __FreeBSD_version < 500014
+	.d_bmaj		-1
+#endif
+};
 
 Static struct cdevsw ugen_cdevsw = {
 	.d_version =	D_VERSION,
@@ -168,6 +204,7 @@ Static struct cdevsw ugen_cdevsw = {
 	.d_write =	ugenwrite,
 	.d_ioctl =	ugenioctl,
 	.d_poll =	ugenpoll,
+	.d_purge =	ugenpurge,
 	.d_name =	"ugen",
 #if __FreeBSD_version < 500014
 	.d_bmaj		-1
@@ -250,8 +287,10 @@ USB_ATTACH(ugen)
 
 #if defined(__FreeBSD__)
 	/* the main device, ctrl endpoint */
-	sc->dev = make_dev(&ugen_cdevsw, UGENMINOR(USBDEVUNIT(sc->sc_dev), 0),
-		UID_ROOT, GID_OPERATOR, 0644, "%s", USBDEVNAME(sc->sc_dev));
+	sc->dev = make_dev(&ugenctl_cdevsw,
+	    UGENMINOR(USBDEVUNIT(sc->sc_dev), 0), UID_ROOT, GID_OPERATOR, 0644,
+	    "%s", USBDEVNAME(sc->sc_dev));
+	ugen_make_devnodes(sc);
 #endif
 
 	USB_ATTACH_SUCCESS_RETURN;
@@ -280,6 +319,7 @@ ugen_make_devnodes(struct ugen_softc *sc)
 				UID_ROOT, GID_OPERATOR, 0644,
 				"%s.%d",
 				USBDEVNAME(sc->sc_dev), endptno);
+			dev_depends(sc->dev, dev);
 			if (sc->sc_endpoints[endptno][IN].sc != NULL)
 				sc->sc_endpoints[endptno][IN].dev = dev;
 			if (sc->sc_endpoints[endptno][OUT].sc != NULL)
@@ -331,10 +371,6 @@ ugen_set_config(struct ugen_softc *sc, int configno)
 	DPRINTFN(1,("ugen_set_config: %s to configno %d, sc=%p\n",
 		    USBDEVNAME(sc->sc_dev), configno, sc));
 
-#if defined(__FreeBSD__)
-	ugen_destroy_devnodes(sc);
-#endif
-
 	/* We start at 1, not 0, because we don't care whether the
 	 * control endpoint is open or not. It is always present.
 	 */
@@ -380,10 +416,6 @@ ugen_set_config(struct ugen_softc *sc, int configno)
 		}
 	}
 
-#if defined(__FreeBSD__)
-	ugen_make_devnodes(sc);
-#endif
-
 	return (USBD_NORMAL_COMPLETION);
 }
 
@@ -414,7 +446,7 @@ ugenopen(struct cdev *dev, int flag, int mode, usb_proc_ptr p)
 
 	if (endpt == USB_CONTROL_ENDPOINT) {
 		sc->sc_is_open[USB_CONTROL_ENDPOINT] = 1;
-		sc->sc_refcnt++;
+		UGEN_DEV_OPEN(dev, sc);
 		return (0);
 	}
 
@@ -551,7 +583,7 @@ ugenopen(struct cdev *dev, int flag, int mode, usb_proc_ptr p)
 		}
 	}
 	sc->sc_is_open[endpt] = 1;
-	sc->sc_refcnt++;
+	UGEN_DEV_OPEN(dev, sc);
 	return (0);
 }
 
@@ -569,6 +601,12 @@ ugenclose(struct cdev *dev, int flag, int mode, usb_proc_ptr p)
 	DPRINTFN(5, ("ugenclose: flag=%d, mode=%d, unit=%d, endpt=%d\n",
 		     flag, mode, UGENUNIT(dev), endpt));
 
+
+#if defined(__NetBSD__) || defined(__OpenBSD__)
+	if (sc->sc_dying)
+		wakeup(&sc->sc_dying);
+#endif
+
 #ifdef DIAGNOSTIC
 	if (!sc->sc_is_open[endpt]) {
 		printf("ugenclose: not open\n");
@@ -579,8 +617,7 @@ ugenclose(struct cdev *dev, int flag, int mode, usb_proc_ptr p)
 	if (endpt == USB_CONTROL_ENDPOINT) {
 		DPRINTFN(5, ("ugenclose: close control\n"));
 		sc->sc_is_open[endpt] = 0;
-		if (--sc->sc_refcnt == 0)
-			usb_detach_wakeup(USBDEV(sc->sc_dev));
+		UGEN_DEV_CLOSE(dev, sc);
 		return (0);
 	}
 
@@ -625,8 +662,7 @@ ugenclose(struct cdev *dev, int flag, int mode, usb_proc_ptr p)
 
 	}
 	sc->sc_is_open[endpt] = 0;
-	if (--sc->sc_refcnt == 0)
-		usb_detach_wakeup(USBDEV(sc->sc_dev));
+	UGEN_DEV_CLOSE(dev, sc);
 
 	return (0);
 }
@@ -821,7 +857,9 @@ ugenread(struct cdev *dev, struct uio *uio, int flag)
 
 	USB_GET_SC(ugen, UGENUNIT(dev), sc);
 
+	UGEN_DEV_REF(dev, sc);
 	error = ugen_do_read(sc, endpt, uio, flag);
+	UGEN_DEV_RELE(dev, sc);
 	return (error);
 }
 
@@ -915,7 +953,9 @@ ugenwrite(struct cdev *dev, struct uio *uio, int flag)
 
 	USB_GET_SC(ugen, UGENUNIT(dev), sc);
 
+	UGEN_DEV_REF(dev, sc);
 	error = ugen_do_write(sc, endpt, uio, flag);
+	UGEN_DEV_RELE(dev, sc);
 	return (error);
 }
 
@@ -937,14 +977,27 @@ ugen_activate(device_ptr_t self, enum devact act)
 }
 #endif
 
+#ifdef __FreeBSD__
+void
+ugenpurge(struct cdev *dev)
+{
+	int endpt = UGENENDPOINT(dev);
+	struct ugen_softc *sc;
+
+	if (endpt == USB_CONTROL_ENDPOINT)
+		return;
+	USB_GET_SC(ugen, UGENUNIT(dev), sc);
+	wakeup(&sc->sc_endpoints[endpt][IN]);
+}
+#endif
+
 USB_DETACH(ugen)
 {
 	USB_DETACH_START(ugen, sc);
 	struct ugen_endpoint *sce;
 	int i, dir;
-	int s;
 #if defined(__NetBSD__) || defined(__OpenBSD__)
-	int maj, mn;
+	int maj, mn, c, s;
 #endif
 
 #if defined(__NetBSD__) || defined(__OpenBSD__)
@@ -967,6 +1020,7 @@ USB_DETACH(ugen)
 		}
 	}
 
+#if defined(__NetBSD__) || defined(__OpenBSD__)
 	s = splusb();
 	if (sc->sc_refcnt > 0) {
 		/* Wake everyone */
@@ -978,7 +1032,17 @@ USB_DETACH(ugen)
 	}
 	splx(s);
 
-#if defined(__NetBSD__) || defined(__OpenBSD__)
+	/* Wait for opens to go away. */
+	do {
+		c = 0;
+		for (i = 0; i < USB_MAX_ENDPOINTS; i++) {
+			if (sc->sc_is_open[i])
+				c++;
+		}
+		if (c != 0)
+			tsleep(&sc->sc_dying, PZERO, "ugendr", hz);
+	} while (c != 0);
+
 	/* locate the major number */
 	for (maj = 0; maj < nchrdev; maj++)
 		if (cdevsw[maj].d_open == ugenopen)
@@ -990,7 +1054,6 @@ USB_DETACH(ugen)
 #elif defined(__FreeBSD__)
 	/* destroy the device for the control endpoint */
 	destroy_dev(sc->dev);
-	ugen_destroy_devnodes(sc);
 #endif
 
 	return (0);
@@ -1285,9 +1348,15 @@ ugen_do_ioctl(struct ugen_softc *sc, int endpt, u_long cmd,
 	case USB_SET_CONFIG:
 		if (!(flag & FWRITE))
 			return (EPERM);
+#if defined(__FreeBSD__)
+		ugen_destroy_devnodes(sc);
+#endif
 		err = ugen_set_config(sc, *(int *)addr);
 		switch (err) {
 		case USBD_NORMAL_COMPLETION:
+#if defined(__FreeBSD__)
+			ugen_make_devnodes(sc);
+#endif
 			break;
 		case USBD_IN_USE:
 			return (EBUSY);
@@ -1493,7 +1562,9 @@ ugenioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, usb_proc_ptr p)
 
 	USB_GET_SC(ugen, UGENUNIT(dev), sc);
 
+	UGEN_DEV_REF(dev, sc);
 	error = ugen_do_ioctl(sc, endpt, cmd, addr, flag, p);
+	UGEN_DEV_RELE(dev, sc);
 	return (error);
 }