1 files changed, 85 insertions, 27 deletions

diff --git a/freebsd/sys/kern/subr_bus.c b/freebsd/sys/kern/subr_bus.c
index 8076e7e3..0626ec0a 100644
--- a/freebsd/sys/kern/subr_bus.c
+++ b/freebsd/sys/kern/subr_bus.c
@@ -1863,6 +1863,8 @@ make_device(device_t parent, const char *name, int unit)
 			return (NULL);
 		}
 	}
+	if (parent != NULL && device_has_quiet_children(parent))
+		dev->flags |= DF_QUIET | DF_QUIET_CHILDREN;
 	dev->ivars = NULL;
 	dev->softc = NULL;
 
@@ -2688,6 +2690,15 @@ device_quiet(device_t dev)
 }
 
 /**
+ * @brief Set the DF_QUIET_CHILDREN flag for the device
+ */
+void
+device_quiet_children(device_t dev)
+{
+	dev->flags |= DF_QUIET_CHILDREN;
+}
+
+/**
  * @brief Clear the DF_QUIET flag for the device
  */
 void
@@ -2697,6 +2708,15 @@ device_verbose(device_t dev)
 }
 
 /**
+ * @brief Return non-zero if the DF_QUIET_CHIDLREN flag is set on the device
+ */
+int
+device_has_quiet_children(device_t dev)
+{
+	return ((dev->flags & DF_QUIET_CHILDREN) != 0);
+}
+
+/**
  * @brief Return non-zero if the DF_QUIET flag is set on the device
  */
 int
@@ -3760,7 +3780,11 @@ bus_generic_detach(device_t dev)
 	if (dev->state != DS_ATTACHED)
 		return (EBUSY);
 
-	TAILQ_FOREACH(child, &dev->children, link) {
+	/*
+	 * Detach children in the reverse order.
+	 * See bus_generic_suspend for details.
+	 */
+	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
 		if ((error = device_detach(child)) != 0)
 			return (error);
 	}
@@ -3780,7 +3804,11 @@ bus_generic_shutdown(device_t dev)
 {
 	device_t child;
 
-	TAILQ_FOREACH(child, &dev->children, link) {
+	/*
+	 * Shut down children in the reverse order.
+	 * See bus_generic_suspend for details.
+	 */
+	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
 		device_shutdown(child);
 	}
 
@@ -3833,15 +3861,23 @@ int
 bus_generic_suspend(device_t dev)
 {
 	int		error;
-	device_t	child, child2;
+	device_t	child;
 
-	TAILQ_FOREACH(child, &dev->children, link) {
+	/*
+	 * Suspend children in the reverse order.
+	 * For most buses all children are equal, so the order does not matter.
+	 * Other buses, such as acpi, carefully order their child devices to
+	 * express implicit dependencies between them.  For such buses it is
+	 * safer to bring down devices in the reverse order.
+	 */
+	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
 		error = BUS_SUSPEND_CHILD(dev, child);
-		if (error) {
-			for (child2 = TAILQ_FIRST(&dev->children);
-			     child2 && child2 != child;
-			     child2 = TAILQ_NEXT(child2, link))
-				BUS_RESUME_CHILD(dev, child2);
+		if (error != 0) {
+			child = TAILQ_NEXT(child, link);
+			if (child != NULL) {
+				TAILQ_FOREACH_FROM(child, &dev->children, link)
+					BUS_RESUME_CHILD(dev, child);
+			}
 			return (error);
 		}
 	}
@@ -5285,8 +5321,9 @@ sysctl_devices(SYSCTL_HANDLER_ARGS)
 	u_int			namelen = arg2;
 	int			index;
 	device_t		dev;
-	struct u_device		udev;	/* XXX this is a bit big */
+	struct u_device		*udev;
 	int			error;
+	char			*walker, *ep;
 
 	if (namelen != 2)
 		return (EINVAL);
@@ -5307,24 +5344,45 @@ sysctl_devices(SYSCTL_HANDLER_ARGS)
 		return (ENOENT);
 
 	/*
-	 * Populate the return array.
+	 * Populate the return item, careful not to overflow the buffer.
 	 */
-	bzero(&udev, sizeof(udev));
-	udev.dv_handle = (uintptr_t)dev;
-	udev.dv_parent = (uintptr_t)dev->parent;
-	if (dev->nameunit != NULL)
-		strlcpy(udev.dv_name, dev->nameunit, sizeof(udev.dv_name));
-	if (dev->desc != NULL)
-		strlcpy(udev.dv_desc, dev->desc, sizeof(udev.dv_desc));
-	if (dev->driver != NULL && dev->driver->name != NULL)
-		strlcpy(udev.dv_drivername, dev->driver->name,
-		    sizeof(udev.dv_drivername));
-	bus_child_pnpinfo_str(dev, udev.dv_pnpinfo, sizeof(udev.dv_pnpinfo));
-	bus_child_location_str(dev, udev.dv_location, sizeof(udev.dv_location));
-	udev.dv_devflags = dev->devflags;
-	udev.dv_flags = dev->flags;
-	udev.dv_state = dev->state;
-	error = SYSCTL_OUT(req, &udev, sizeof(udev));
+	udev = malloc(sizeof(*udev), M_BUS, M_WAITOK | M_ZERO);
+	if (udev == NULL)
+		return (ENOMEM);
+	udev->dv_handle = (uintptr_t)dev;
+	udev->dv_parent = (uintptr_t)dev->parent;
+	udev->dv_devflags = dev->devflags;
+	udev->dv_flags = dev->flags;
+	udev->dv_state = dev->state;
+	walker = udev->dv_fields;
+	ep = walker + sizeof(udev->dv_fields);
+#define CP(src)						\
+	if ((src) == NULL)				\
+		*walker++ = '\0';			\
+	else {						\
+		strlcpy(walker, (src), ep - walker);	\
+		walker += strlen(walker) + 1;		\
+	}						\
+	if (walker >= ep)				\
+		break;
+
+	do {
+		CP(dev->nameunit);
+		CP(dev->desc);
+		CP(dev->driver != NULL ? dev->driver->name : NULL);
+		bus_child_pnpinfo_str(dev, walker, ep - walker);
+		walker += strlen(walker) + 1;
+		if (walker >= ep)
+			break;
+		bus_child_location_str(dev, walker, ep - walker);
+		walker += strlen(walker) + 1;
+		if (walker >= ep)
+			break;
+		*walker++ = '\0';
+	} while (0);
+#undef CP
+	error = SYSCTL_OUT(req, udev, sizeof(*udev));
+	free(udev, M_BUS);
 	return (error);
 }