Example #1
0
static void
vtpci_probe_and_attach_child(struct vtpci_softc *sc)
{
	device_t dev, child;

	dev = sc->vtpci_dev;
	child = sc->vtpci_child_dev;

	if (child == NULL)
		return;

	if (device_get_state(child) != DS_NOTPRESENT)
		return;

	if (device_probe(child) != 0)
		return;

	vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_DRIVER);
	if (device_attach(child) != 0) {
		vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_FAILED);
		vtpci_reset(sc);
		vtpci_release_child_resources(sc);
		/* Reset status for future attempt. */
		vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_ACK);
	} else {
		vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_DRIVER_OK);
		VIRTIO_ATTACH_COMPLETED(child);
	}
}
Example #2
0
/*
 * Locate the ACPI timer using the FADT, set up and allocate the I/O resources
 * we will be using.
 */
static int
acpi_timer_identify(driver_t *driver, device_t parent)
{
    device_t dev;

    /*
     * Just try once, do nothing if the 'acpi' bus is rescanned.
     */
    if (device_get_state(parent) == DS_ATTACHED)
	return (0);

    ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);

    if (acpi_disabled("timer") || (acpi_quirks & ACPI_Q_TIMER) ||
	acpi_timer_dev)
	return (ENXIO);

    if ((dev = BUS_ADD_CHILD(parent, parent, 0, "acpi_timer", 0)) == NULL) {
	device_printf(parent, "could not add acpi_timer0\n");
	return (ENXIO);
    }
    acpi_timer_dev = dev;

    return (0);
}
Example #3
0
static int
isahint_identify(driver_t *driver, device_t parent)
{
	int i;
	static char buf[] = "isaXXX";

	/*
	 * If the parent bus is already attached we are being called to
	 * rescan.  We do not suppot rescanning the hints, just return
	 * success.
	 */
	if (device_get_state(parent) == DS_ATTACHED)
		return(0);
	if (device_get_state(parent) == DS_INPROGRESS)
		return(0);

	/*
	 * Add all devices configured to be attached to parent.
	 */
	ksprintf(buf, "isa%d", device_get_unit(parent));
	for (i = resource_query_string(-1, "at", buf);
	     i != -1;
	     i = resource_query_string(i, "at", buf)) {
		if (strcmp(resource_query_name(i), "atkbd") == 0)
			continue;	/* old GENERIC kludge */
		isahint_add_device(parent,
				   resource_query_name(i),
				   resource_query_unit(i));
	}

	/*
	 * and isa?
	 */
	for (i = resource_query_string(-1, "at", "isa");
	     i != -1;
	     i = resource_query_string(i, "at", "isa")) {
		if (strcmp(resource_query_name(i), "atkbd") == 0)
			continue;	/* old GENERIC kludge */
		isahint_add_device(parent,
				   resource_query_name(i),
				   resource_query_unit(i));
	}
	return(0);
}
Example #4
0
/*
 * Locate the ACPI timer using the FADT, set up and allocate the I/O resources
 * we will be using.
 */
static int
acpi_hpet_identify(driver_t *driver, device_t parent)
{
	ACPI_TABLE_HPET *hpet;
	ACPI_TABLE_HEADER *hdr;
	ACPI_STATUS status;
	device_t child;

	/*
	 * Just try once, do nothing if the 'acpi' bus is rescanned.
	 */
	if (device_get_state(parent) == DS_ATTACHED)
		return 0;

	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);

	/* Only one HPET device can be added. */
	if (devclass_get_device(acpi_hpet_devclass, 0))
		return ENXIO;

	/* Currently, ID and minimum clock tick info is unused. */

	status = AcpiGetTable(ACPI_SIG_HPET, 1, &hdr);
	if (ACPI_FAILURE(status))
		return ENXIO;

	/*
	 * The unit number could be derived from hdr->Sequence but we only
	 * support one HPET device.
	 */
	hpet = (ACPI_TABLE_HPET *)hdr;
	if (hpet->Sequence != 0) {
		kprintf("ACPI HPET table warning: Sequence is non-zero (%d)\n",
			hpet->Sequence);
	}

	child = BUS_ADD_CHILD(parent, parent, 0, "acpi_hpet", 0);
	if (child == NULL) {
		device_printf(parent, "%s: can't add acpi_hpet0\n", __func__);
		return ENXIO;
	}

	/* Record a magic value so we can detect this device later. */
	acpi_set_magic(child, (uintptr_t)&acpi_hpet_devclass);

	acpi_hpet_res_start = hpet->Address.Address;
	if (bus_set_resource(child, SYS_RES_MEMORY, 0,
			     hpet->Address.Address, HPET_MEM_WIDTH, -1)) {
		device_printf(child, "could not set iomem resources: "
			      "0x%jx, %d\n", (uintmax_t)hpet->Address.Address,
			      HPET_MEM_WIDTH);
		return ENOMEM;
	}
	return 0;
}
Example #5
0
static void
cardbus_driver_added(device_t cbdev, driver_t *driver)
{
	int numdevs;
	device_t *devlist;
	device_t dev;
	int i;
	struct cardbus_devinfo *dinfo;

	DEVICE_IDENTIFY(driver, cbdev);
	if (device_get_children(cbdev, &devlist, &numdevs) != 0)
		return;

	/*
	 * If there are no drivers attached, but there are children,
	 * then power the card up.
	 */
	for (i = 0; i < numdevs; i++) {
		dev = devlist[i];
		if (device_get_state(dev) != DS_NOTPRESENT)
		    break;
	}
	if (i > 0 && i == numdevs)
		POWER_ENABLE_SOCKET(device_get_parent(cbdev), cbdev);
	for (i = 0; i < numdevs; i++) {
		dev = devlist[i];
		if (device_get_state(dev) != DS_NOTPRESENT)
			continue;
		dinfo = device_get_ivars(dev);
		pci_print_verbose(&dinfo->pci);
		if (bootverbose)
			printf("pci%d:%d:%d:%d: reprobing on driver added\n",
			    dinfo->pci.cfg.domain, dinfo->pci.cfg.bus,
			    dinfo->pci.cfg.slot, dinfo->pci.cfg.func);
		pci_cfg_restore(dinfo->pci.cfg.dev, &dinfo->pci);
		if (device_probe_and_attach(dev) != 0)
			pci_cfg_save(dev, &dinfo->pci, 1);
	}
	free(devlist, M_TEMP);
}
Example #6
0
static int
rp_pcishutdown(device_t dev)
{
	CONTROLLER_t	*ctlp;

	if (device_get_state(dev) == DS_BUSY)
		return (EBUSY);

	ctlp = device_get_softc(dev);

	rp_pcireleaseresource(ctlp);

	return (0);
}
Example #7
0
/*
 * Locate the ACPI timer using the FADT, set up and allocate the I/O resources
 * we will be using.
 */
static int
acpi_timer_identify(driver_t *driver, device_t parent)
{
    device_t dev;
    u_long rlen, rstart;
    int rid, rtype;

    /*
     * Just try once, do nothing if the 'acpi' bus is rescanned.
     */
    if (device_get_state(parent) == DS_ATTACHED)
	return (0);

    ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);

    if (acpi_disabled("timer") || (acpi_quirks & ACPI_Q_TIMER) ||
	acpi_timer_dev)
	return (ENXIO);

    if ((dev = BUS_ADD_CHILD(parent, parent, 0, "acpi_timer", 0)) == NULL) {
	device_printf(parent, "could not add acpi_timer0\n");
	return (ENXIO);
    }
    acpi_timer_dev = dev;

    switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) {
    case ACPI_ADR_SPACE_SYSTEM_MEMORY:
	rtype = SYS_RES_MEMORY;
	break;
    case ACPI_ADR_SPACE_SYSTEM_IO:
	rtype = SYS_RES_IOPORT;
	break;
    default:
	return (ENXIO);
    }
    rid = 0;
    rlen = AcpiGbl_FADT.PmTimerLength;
    rstart = AcpiGbl_FADT.XPmTimerBlock.Address;
    if (bus_set_resource(dev, rtype, rid, rstart, rlen, -1)) {
	device_printf(dev, "couldn't set resource (%s 0x%lx+0x%lx)\n",
	    (rtype == SYS_RES_IOPORT) ? "port" : "mem", rstart, rlen);
	return (ENXIO);
    }
    return (0);
}
static int
create_a_copy(device_t atkbdc, device_t me)
{
	device_t psm;
	u_long irq;

	/* find the PS/2 mouse device instance under the keyboard controller */
	psm = device_find_child(atkbdc, PSM_DRIVER_NAME,
				device_get_unit(atkbdc));
	if (psm == NULL)
		return ENXIO;
	if (device_get_state(psm) != DS_NOTPRESENT)
		return 0;

	/* move our resource to the found device */
	irq = bus_get_resource_start(me, SYS_RES_IRQ, 0);
	bus_set_resource(psm, SYS_RES_IRQ, KBDC_RID_AUX, irq, 1);

	/* ...then probe and attach it */
	return device_probe_and_attach(psm);
}
static int
psmcpnp_attach(device_t dev)
{
	device_t atkbdc;
	int rid;

	/* find the keyboard controller, which may be on acpi* or isa* bus */
	atkbdc = devclass_get_device(devclass_find(ATKBDC_DRIVER_NAME),
				     device_get_unit(dev));
	if ((atkbdc != NULL) && (device_get_state(atkbdc) == DS_ATTACHED)) {
		create_a_copy(atkbdc, dev);
	} else {
		/*
		 * If we don't have the AT keyboard controller yet,
		 * just reserve the IRQ for later use...
		 * (See psmidentify() above.)
		 */
		rid = 0;
		bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_SHAREABLE);
	}

	return 0;
}
static int
xenbus_probe_children(device_t dev)
{
	device_t *kids;
	struct xenbus_device_ivars *ivars;
	int i, count;

	/*
	 * Probe any new devices and register watches for any that
	 * attach successfully. Since part of the protocol which
	 * establishes a connection with the other end is interrupt
	 * driven, we sleep until the device reaches a stable state
	 * (closed or connected).
	 */
	if (device_get_children(dev, &kids, &count) == 0) {
		for (i = 0; i < count; i++) {
			if (device_get_state(kids[i]) != DS_NOTPRESENT)
				continue;

			if (device_probe_and_attach(kids[i]))
				continue;
			ivars = device_get_ivars(kids[i]);
			register_xenbus_watch(
				&ivars->xd_otherend_watch);
			sx_xlock(&ivars->xd_lock);
			while (ivars->xd_state != XenbusStateClosed
			    && ivars->xd_state != XenbusStateConnected)
				sx_sleep(&ivars->xd_state, &ivars->xd_lock,
				    0, "xdattach", 0);
			sx_xunlock(&ivars->xd_lock);
		}
		free(kids, M_TEMP);
	}

	return (0);
}
Example #11
0
/*
 * Quiz the PnP BIOS, build a list of PNP IDs and resource data.
 */
static int
pnpbios_identify(driver_t *driver, device_t parent)
{
    struct PnPBIOS_table	*pt = PnPBIOStable;
    struct bios_args		args;
    struct pnp_sysdev		*pd;
    struct pnp_sysdevargs	*pda;
    uint16_t			ndevs, bigdev;
    int				error, currdev;
    uint8_t			*devnodebuf, tag;
    uint32_t			*devid, *compid;
    int				idx, left;
    device_t			dev;

    /*
     * Umm, we aren't going to rescan the PnP BIOS to look for new additions.
     */
    if (device_get_state(parent) == DS_ATTACHED)
	return (0);
        
    /* no PnP BIOS information */
    if (pt == NULL)
	return (ENXIO);

    /* ACPI already active */
    if (devclass_get_softc(devclass_find("ACPI"), 0) != NULL)
	return (ENXIO);
    
    bzero(&args, sizeof(args));
    args.seg.code16.base = BIOS_PADDRTOVADDR(pt->pmentrybase);
    args.seg.code16.limit = 0xffff;		/* XXX ? */
    args.seg.data.base = BIOS_PADDRTOVADDR(pt->pmdataseg);
    args.seg.data.limit = 0xffff;
    args.entry = pt->pmentryoffset;

    if ((error = bios16(&args, PNP_COUNT_DEVNODES, &ndevs, &bigdev)) || (args.r.eax & 0xff))
	kprintf("pnpbios: error %d/%x getting device count/size limit\n", error, args.r.eax);
    ndevs &= 0xff;				/* clear high byte garbage */
    if (bootverbose)
	kprintf("pnpbios: %d devices, largest %d bytes\n", ndevs, bigdev);

    devnodebuf = kmalloc(bigdev + (sizeof(struct pnp_sysdevargs) - sizeof(struct pnp_sysdev)), M_DEVBUF, M_INTWAIT);
    pda = (struct pnp_sysdevargs *)devnodebuf;
    pd = &pda->node;

    for (currdev = 0, left = ndevs; (currdev != 0xff) && (left > 0); left--) {
	bzero(pd, bigdev);
	pda->next = currdev;

	/* get current configuration */
	if ((error = bios16(&args, PNP_GET_DEVNODE, &pda->next, &pda->node, 1))) {
	    kprintf("pnpbios: error %d making BIOS16 call\n", error);
	    break;
	}
	if (bootverbose)
	    kprintf("pnp_get_devnode cd=%d nxt=%d size=%d handle=%d devid=%08x type=%02x%02x%02x, attrib=%04x\n", currdev, pda->next, pd->size, pd->handle, pd->devid, pd->type[0], pd->type[1], pd->type[2], pd->attrib);

	if ((error = (args.r.eax & 0xff))) {
	    if (bootverbose)
		kprintf("pnpbios: %s 0x%x fetching node %d\n", error & 0x80 ? "error" : "warning", error, currdev);
	    if (error & 0x80) 
		break;
	}
	currdev = pda->next;
	if (pd->size < sizeof(struct pnp_sysdev)) {
	    kprintf("pnpbios: bogus system node data, aborting scan\n");
	    break;
	}
	
	/*
	 * Ignore PICs so that we don't have to worry about the PICs
	 * claiming IRQs to prevent their use.  The PIC drivers
	 * already ensure that invalid IRQs are not used.
	 */
	if (!strcmp(pnp_eisaformat(pd->devid), "PNP0000"))	/* ISA PIC */
	    continue;
	if (!strcmp(pnp_eisaformat(pd->devid), "PNP0003"))	/* APIC */
	    continue;

	/* Add the device and parse its resources */
	dev = BUS_ADD_CHILD(parent, parent, ISA_ORDER_PNP, NULL, -1);
	isa_set_vendorid(dev, pd->devid);
	isa_set_logicalid(dev, pd->devid);

	/*
	 * It appears that some PnP BIOS doesn't allow us to re-enable
	 * the embedded system device once it is disabled.  We shall
	 * mark all system device nodes as "cannot be disabled", regardless
	 * of actual settings in the device attribute byte.  XXX
	 */
#if 0
	isa_set_configattr(dev, 
	    ((pd->attrib & PNPATTR_NODISABLE) ?  0 : ISACFGATTR_CANDISABLE) |
	    ((!(pd->attrib & PNPATTR_NOCONFIG) && 
		PNPATTR_CONFIG(pd->attrib) != PNPATTR_CONFIG_STATIC)
		? ISACFGATTR_DYNAMIC : 0));
#endif
	isa_set_configattr(dev, 
	    (!(pd->attrib & PNPATTR_NOCONFIG) && 
		PNPATTR_CONFIG(pd->attrib) != PNPATTR_CONFIG_STATIC)
		? ISACFGATTR_DYNAMIC : 0);

	ISA_SET_CONFIG_CALLBACK(parent, dev, pnpbios_set_config, 0);
	pnp_parse_resources(dev, &pd->devdata[0],
			    pd->size - sizeof(struct pnp_sysdev), 0);
	if (!device_get_desc(dev))
	    device_set_desc_copy(dev, pnp_eisaformat(pd->devid));

	/* Find device IDs */
	devid = &pd->devid;
	compid = NULL;

	/* look for a compatible device ID too */
	left = pd->size - sizeof(struct pnp_sysdev);
	idx = 0;
	while (idx < left) {
	    tag = pd->devdata[idx++];
	    if (PNP_RES_TYPE(tag) == 0) {
		/* Small resource */
		switch (PNP_SRES_NUM(tag)) {
		case PNP_TAG_COMPAT_DEVICE:
		    compid = (uint32_t *)(pd->devdata + idx);
		    if (bootverbose)
			kprintf("pnpbios: node %d compat ID 0x%08x\n", pd->handle, *compid);
		    /* FALLTHROUGH */
		case PNP_TAG_END:
		    idx = left;
		    break;
		default:
		    idx += PNP_SRES_LEN(tag);
		    break;
		}
	    } else
		/* Large resource, skip it */
		idx += *(uint16_t *)(pd->devdata + idx) + 2;
	}
	if (bootverbose) {
	    kprintf("pnpbios: handle %d device ID %s (%08x)", 
		   pd->handle, pnp_eisaformat(*devid), *devid);
	    if (compid != NULL)
		kprintf(" compat ID %s (%08x)",
		       pnp_eisaformat(*compid), *compid);
	    kprintf("\n");
	}
    }
    return (0);
}
Example #12
0
/**
 * \brief Verify the existance of attached device instances and perform
 *        probe/attach processing for newly arrived devices.
 *
 * \param dev  The NewBus device representing this XenBus bus.
 *
 * \return  On success, 0. Otherwise an errno value indicating the
 *          type of failure.
 */
static int
xenbusb_probe_children(device_t dev)
{
	device_t *kids;
	struct xenbus_device_ivars *ivars;
	int i, count, error;

	if (device_get_children(dev, &kids, &count) == 0) {
		for (i = 0; i < count; i++) {
			if (device_get_state(kids[i]) != DS_NOTPRESENT) {
				/*
				 * We already know about this one.
				 * Make sure it's still here.
				 */
				xenbusb_verify_device(dev, kids[i]);
				continue;
			}

			error = device_probe_and_attach(kids[i]);
			if (error == ENXIO) {
				struct xenbusb_softc *xbs;

				/*
				 * We don't have a PV driver for this device.
				 * However, an emulated device we do support
				 * may share this backend.  Hide the node from
				 * XenBus until the next rescan, but leave it's
				 * state unchanged so we don't inadvertently
				 * prevent attachment of any emulated device.
				 */
				xenbusb_delete_child(dev, kids[i]);

				/*
				 * Since the XenStore state of this device
				 * still indicates a pending attach, manually
				 * release it's hold on the boot process.
				 */
				xbs = device_get_softc(dev);
				xenbusb_release_confighook(xbs);

				continue;
			} else if (error) {
				/*
				 * Transition device to the closed state
				 * so the world knows that attachment will
				 * not occur.
				 */
				xenbus_set_state(kids[i], XenbusStateClosed);

				/*
				 * Remove our record of this device.
				 * So long as it remains in the closed
				 * state in the XenStore, we will not find
				 * it again.  The state will only change
				 * if the control domain actively reconfigures
				 * this device.
				 */
				xenbusb_delete_child(dev, kids[i]);

				continue;
			}
			/*
			 * Augment default newbus provided dynamic sysctl
			 * variables with the standard ivar contents of
			 * XenBus devices.
			 */
			xenbusb_device_sysctl_init(kids[i]);

			/*
			 * Now that we have a driver managing this device
			 * that can receive otherend state change events,
			 * hook up a watch for them.
			 */
			ivars = device_get_ivars(kids[i]);
			xs_register_watch(&ivars->xd_otherend_watch);
			xs_register_watch(&ivars->xd_local_watch);
		}
		free(kids, M_TEMP);
	}

	return (0);
}
Example #13
0
static int
orm_identify(driver_t* driver, device_t parent)
{
	bus_space_handle_t	bh;
	bus_space_tag_t		bt;
	device_t		child;
	u_int32_t		chunk = IOMEM_START;
	struct resource		*res;
	int			rid;
	u_int32_t		rom_size;
	struct orm_softc	*sc;
	u_int8_t		buf[3];

	/*
	 * rescanning the isa bus, do nothing
	 */
	if (device_get_state(parent) == DS_ATTACHED)
		return (0);

	/*
	 * Otherwise see if it exists
	 */
	child = BUS_ADD_CHILD(parent, parent, ISA_ORDER_SENSITIVE, "orm", -1);
	device_set_driver(child, driver);
	isa_set_logicalid(child, ORM_ID);
	isa_set_vendorid(child, ORM_ID);
	sc = device_get_softc(child);
	sc->rnum = 0;
	while (chunk < IOMEM_END) {
		bus_set_resource(child, SYS_RES_MEMORY, sc->rnum, chunk,
		    IOMEM_STEP, -1);
		rid = sc->rnum;
		res = bus_alloc_resource_any(child, SYS_RES_MEMORY, &rid,
		    RF_ACTIVE);
		if (res == NULL) {
			bus_delete_resource(child, SYS_RES_MEMORY, sc->rnum);
			chunk += IOMEM_STEP;
			continue;
		}
		bt = rman_get_bustag(res);
		bh = rman_get_bushandle(res);
		bus_space_read_region_1(bt, bh, 0, buf, sizeof(buf));

		/*
		 * We need to release and delete the resource since we're
		 * changing its size, or the rom isn't there.  There
		 * is a checksum field in the ROM to prevent false
		 * positives.  However, some common hardware (IBM thinkpads)
		 * neglects to put a valid checksum in the ROM, so we do
		 * not double check the checksum here.  On the ISA bus
		 * areas that have no hardware read back as 0xff, so the
		 * tests to see if we have 0x55 followed by 0xaa are
		 * generally sufficient.
		 */
		bus_release_resource(child, SYS_RES_MEMORY, rid, res);
		bus_delete_resource(child, SYS_RES_MEMORY, sc->rnum);
		if (buf[0] != 0x55 || buf[1] != 0xAA || (buf[2] & 0x03) != 0) {
			chunk += IOMEM_STEP;
			continue;
		}
		rom_size = buf[2] << 9;
		bus_set_resource(child, SYS_RES_MEMORY, sc->rnum, chunk,
		    rom_size, -1);
		rid = sc->rnum;
		res = bus_alloc_resource_any(child, SYS_RES_MEMORY, &rid, 0);
		if (res == NULL) {
			bus_delete_resource(child, SYS_RES_MEMORY, sc->rnum);
			chunk += IOMEM_STEP;
			continue;
		}
		sc->rid[sc->rnum] = rid;
		sc->res[sc->rnum] = res;
		sc->rnum++;
		chunk += rom_size;
	}

	/*
	 * note: sc becomes invalid after we delete the child.
	 */
	if (sc->rnum == 0) {
		device_delete_child(parent, child);
		return (ENXIO);
	}
	if (sc->rnum == 1)
		device_set_desc(child, "ISA Option ROM");
	else
		device_set_desc(child, "ISA Option ROMs");
	return (0);
}
static int
xenbus_resume(device_t dev)
{
	device_t *kids;
	struct xenbus_device_ivars *ivars;
	int i, count, error;
	char *statepath;

	xb_init_comms();
	xs_resume();

	/*
	 * We must re-examine each device and find the new path for
	 * its backend.
	 */
	if (device_get_children(dev, &kids, &count) == 0) {
		for (i = 0; i < count; i++) {
			if (device_get_state(kids[i]) == DS_NOTPRESENT)
				continue;

			ivars = device_get_ivars(kids[i]);

			unregister_xenbus_watch(
				&ivars->xd_otherend_watch);
			ivars->xd_state = XenbusStateInitialising;

			/*
			 * Find the new backend details and
			 * re-register our watch.
			 */
			free(ivars->xd_otherend_path, M_DEVBUF);
			error = xenbus_gather(XBT_NIL, ivars->xd_node,
			    "backend-id", "%i", &ivars->xd_otherend_id,
			    "backend", NULL, &ivars->xd_otherend_path,
			    NULL);
			if (error)
				return (error);

			DEVICE_RESUME(kids[i]);

			statepath = malloc(strlen(ivars->xd_otherend_path)
			    + strlen("/state") + 1, M_DEVBUF, M_WAITOK);
			sprintf(statepath, "%s/state", ivars->xd_otherend_path);

			free(ivars->xd_otherend_watch.node, M_DEVBUF);
			ivars->xd_otherend_watch.node = statepath;
			register_xenbus_watch(
				&ivars->xd_otherend_watch);

#if 0
			/*
			 * Can't do this yet since we are running in
			 * the xenwatch thread and if we sleep here,
			 * we will stop delivering watch notifications
			 * and the device will never come back online.
			 */
			sx_xlock(&ivars->xd_lock);
			while (ivars->xd_state != XenbusStateClosed
			    && ivars->xd_state != XenbusStateConnected)
				sx_sleep(&ivars->xd_state, &ivars->xd_lock,
				    0, "xdresume", 0);
			sx_xunlock(&ivars->xd_lock);
#endif
		}
		free(kids, M_TEMP);
	}

	return (0);
}