From 95efb20c714800de7eaf991f19dab6e7a29d5364 Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Wed, 24 Apr 2013 14:29:08 +0200 Subject: usb-host: live migration support for the libusb version Signed-off-by: Gerd Hoffmann --- hw/usb/host-libusb.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 49 insertions(+), 5 deletions(-) (limited to 'hw/usb/host-libusb.c') diff --git a/hw/usb/host-libusb.c b/hw/usb/host-libusb.c index d1186b8a9f..ee67c4c23e 100644 --- a/hw/usb/host-libusb.c +++ b/hw/usb/host-libusb.c @@ -94,7 +94,8 @@ struct USBHostDevice { } ifs[USB_MAX_INTERFACES]; /* callbacks & friends */ - QEMUBH *bh; + QEMUBH *bh_nodev; + QEMUBH *bh_postld; Notifier exit; /* request queues */ @@ -835,10 +836,10 @@ static void usb_host_nodev_bh(void *opaque) static void usb_host_nodev(USBHostDevice *s) { - if (!s->bh) { - s->bh = qemu_bh_new(usb_host_nodev_bh, s); + if (!s->bh_nodev) { + s->bh_nodev = qemu_bh_new(usb_host_nodev_bh, s); } - qemu_bh_schedule(s->bh); + qemu_bh_schedule(s->bh_nodev); } static void usb_host_exit_notifier(struct Notifier *n, void *data) @@ -1228,9 +1229,52 @@ static void usb_host_handle_reset(USBDevice *udev) usb_host_ep_update(s); } +/* + * This is *NOT* about restoring state. We have absolutely no idea + * what state the host device is in at the moment and whenever it is + * still present in the first place. Attemping to contine where we + * left off is impossible. + * + * What we are going to to to here is emulate a surprise removal of + * the usb device passed through, then kick host scan so the device + * will get re-attached (and re-initialized by the guest) in case it + * is still present. + * + * As the device removal will change the state of other devices (usb + * host controller, most likely interrupt controller too) we have to + * wait with it until *all* vmstate is loaded. Thus post_load just + * kicks a bottom half which then does the actual work. + */ +static void usb_host_post_load_bh(void *opaque) +{ + USBHostDevice *dev = opaque; + USBDevice *udev = USB_DEVICE(dev); + + if (dev->dh != NULL) { + usb_host_close(dev); + } + if (udev->attached) { + usb_device_detach(udev); + } + usb_host_auto_check(NULL); +} + +static int usb_host_post_load(void *opaque, int version_id) +{ + USBHostDevice *dev = opaque; + + if (!dev->bh_postld) { + dev->bh_postld = qemu_bh_new(usb_host_post_load_bh, dev); + } + qemu_bh_schedule(dev->bh_postld); + return 0; +} + static const VMStateDescription vmstate_usb_host = { .name = "usb-host", - .unmigratable = 1, + .version_id = 1, + .minimum_version_id = 1, + .post_load = usb_host_post_load, .fields = (VMStateField[]) { VMSTATE_USB_DEVICE(parent_obj, USBHostDevice), VMSTATE_END_OF_LIST() -- cgit v1.2.1