diff --git a/hw/block/dataplane/xen-block.c b/hw/block/dataplane/xen-block.c index 3b9caeb2fa..288a87a814 100644 --- a/hw/block/dataplane/xen-block.c +++ b/hw/block/dataplane/xen-block.c @@ -685,12 +685,24 @@ void xen_block_dataplane_stop(XenBlockDataPlane *dataplane) return; } + xendev = dataplane->xendev; + aio_context_acquire(dataplane->ctx); + if (dataplane->event_channel) { + /* Only reason for failure is a NULL channel */ + xen_device_set_event_channel_context(xendev, dataplane->event_channel, + qemu_get_aio_context(), + &error_abort); + } /* Xen doesn't have multiple users for nodes, so this can't fail */ blk_set_aio_context(dataplane->blk, qemu_get_aio_context(), &error_abort); aio_context_release(dataplane->ctx); - xendev = dataplane->xendev; + /* + * Now that the context has been moved onto the main thread, cancel + * further processing. + */ + qemu_bh_cancel(dataplane->bh); if (dataplane->event_channel) { Error *local_err = NULL; @@ -807,7 +819,7 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane, } dataplane->event_channel = - xen_device_bind_event_channel(xendev, dataplane->ctx, event_channel, + xen_device_bind_event_channel(xendev, event_channel, xen_block_dataplane_event, dataplane, &local_err); if (local_err) { @@ -818,7 +830,11 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane, aio_context_acquire(dataplane->ctx); /* If other users keep the BlockBackend in the iothread, that's ok */ blk_set_aio_context(dataplane->blk, dataplane->ctx, NULL); + /* Only reason for failure is a NULL channel */ + xen_device_set_event_channel_context(xendev, dataplane->event_channel, + dataplane->ctx, &error_abort); aio_context_release(dataplane->ctx); + return; stop: diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c index 919e66162a..18237b34ea 100644 --- a/hw/xen/xen-bus.c +++ b/hw/xen/xen-bus.c @@ -1089,8 +1089,26 @@ static void xen_device_event(void *opaque) } } +void xen_device_set_event_channel_context(XenDevice *xendev, + XenEventChannel *channel, + AioContext *ctx, + Error **errp) +{ + if (!channel) { + error_setg(errp, "bad channel"); + return; + } + + if (channel->ctx) + aio_set_fd_handler(channel->ctx, xenevtchn_fd(channel->xeh), true, + NULL, NULL, NULL, NULL); + + channel->ctx = ctx; + aio_set_fd_handler(channel->ctx, xenevtchn_fd(channel->xeh), true, + xen_device_event, NULL, xen_device_poll, channel); +} + XenEventChannel *xen_device_bind_event_channel(XenDevice *xendev, - AioContext *ctx, unsigned int port, XenEventHandler handler, void *opaque, Error **errp) @@ -1116,9 +1134,10 @@ XenEventChannel *xen_device_bind_event_channel(XenDevice *xendev, channel->handler = handler; channel->opaque = opaque; - channel->ctx = ctx; - aio_set_fd_handler(channel->ctx, xenevtchn_fd(channel->xeh), true, - xen_device_event, NULL, xen_device_poll, channel); + /* Only reason for failure is a NULL channel */ + xen_device_set_event_channel_context(xendev, channel, + qemu_get_aio_context(), + &error_abort); QLIST_INSERT_HEAD(&xendev->event_channels, channel, list); diff --git a/include/hw/xen/xen-bus.h b/include/hw/xen/xen-bus.h index 3d5532258d..c18c1372af 100644 --- a/include/hw/xen/xen-bus.h +++ b/include/hw/xen/xen-bus.h @@ -128,10 +128,13 @@ void xen_device_copy_grant_refs(XenDevice *xendev, bool to_domain, typedef bool (*XenEventHandler)(void *opaque); XenEventChannel *xen_device_bind_event_channel(XenDevice *xendev, - AioContext *ctx, unsigned int port, XenEventHandler handler, void *opaque, Error **errp); +void xen_device_set_event_channel_context(XenDevice *xendev, + XenEventChannel *channel, + AioContext *ctx, + Error **errp); void xen_device_notify_event_channel(XenDevice *xendev, XenEventChannel *channel, Error **errp);