diff --git a/hw/block/dataplane/xen-block.c b/hw/block/dataplane/xen-block.c index d8bc39d359..2597f38805 100644 --- a/hw/block/dataplane/xen-block.c +++ b/hw/block/dataplane/xen-block.c @@ -664,6 +664,30 @@ void xen_block_dataplane_destroy(XenBlockDataPlane *dataplane) g_free(dataplane); } +void xen_block_dataplane_detach(XenBlockDataPlane *dataplane) +{ + if (!dataplane || !dataplane->event_channel) { + return; + } + + /* Only reason for failure is a NULL channel */ + xen_device_set_event_channel_context(dataplane->xendev, + dataplane->event_channel, + NULL, &error_abort); +} + +void xen_block_dataplane_attach(XenBlockDataPlane *dataplane) +{ + if (!dataplane || !dataplane->event_channel) { + return; + } + + /* Only reason for failure is a NULL channel */ + xen_device_set_event_channel_context(dataplane->xendev, + dataplane->event_channel, + dataplane->ctx, &error_abort); +} + void xen_block_dataplane_stop(XenBlockDataPlane *dataplane) { XenDevice *xendev; @@ -674,13 +698,11 @@ void xen_block_dataplane_stop(XenBlockDataPlane *dataplane) 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); + if (!blk_in_drain(dataplane->blk)) { + xen_block_dataplane_detach(dataplane); } + + aio_context_acquire(dataplane->ctx); /* 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); @@ -819,11 +841,9 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane, blk_set_aio_context(dataplane->blk, dataplane->ctx, NULL); aio_context_release(old_context); - /* Only reason for failure is a NULL channel */ - aio_context_acquire(dataplane->ctx); - xen_device_set_event_channel_context(xendev, dataplane->event_channel, - dataplane->ctx, &error_abort); - aio_context_release(dataplane->ctx); + if (!blk_in_drain(dataplane->blk)) { + xen_block_dataplane_attach(dataplane); + } return; diff --git a/hw/block/dataplane/xen-block.h b/hw/block/dataplane/xen-block.h index 76dcd51c3d..7b8e9df09f 100644 --- a/hw/block/dataplane/xen-block.h +++ b/hw/block/dataplane/xen-block.h @@ -26,5 +26,7 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane, unsigned int protocol, Error **errp); void xen_block_dataplane_stop(XenBlockDataPlane *dataplane); +void xen_block_dataplane_attach(XenBlockDataPlane *dataplane); +void xen_block_dataplane_detach(XenBlockDataPlane *dataplane); #endif /* HW_BLOCK_DATAPLANE_XEN_BLOCK_H */ diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c index f5a744589d..f099914831 100644 --- a/hw/block/xen-block.c +++ b/hw/block/xen-block.c @@ -189,8 +189,26 @@ static void xen_block_resize_cb(void *opaque) xen_device_backend_printf(xendev, "state", "%u", state); } +/* Suspend request handling */ +static void xen_block_drained_begin(void *opaque) +{ + XenBlockDevice *blockdev = opaque; + + xen_block_dataplane_detach(blockdev->dataplane); +} + +/* Resume request handling */ +static void xen_block_drained_end(void *opaque) +{ + XenBlockDevice *blockdev = opaque; + + xen_block_dataplane_attach(blockdev->dataplane); +} + static const BlockDevOps xen_block_dev_ops = { - .resize_cb = xen_block_resize_cb, + .resize_cb = xen_block_resize_cb, + .drained_begin = xen_block_drained_begin, + .drained_end = xen_block_drained_end, }; static void xen_block_realize(XenDevice *xendev, Error **errp) @@ -242,8 +260,6 @@ static void xen_block_realize(XenDevice *xendev, Error **errp) return; } - blk_set_dev_ops(blk, &xen_block_dev_ops, blockdev); - if (conf->discard_granularity == -1) { conf->discard_granularity = conf->physical_block_size; } @@ -277,6 +293,8 @@ static void xen_block_realize(XenDevice *xendev, Error **errp) blockdev->dataplane = xen_block_dataplane_create(xendev, blk, conf->logical_block_size, blockdev->props.iothread); + + blk_set_dev_ops(blk, &xen_block_dev_ops, blockdev); } static void xen_block_frontend_changed(XenDevice *xendev, diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c index c59850b1de..b8f408c9ed 100644 --- a/hw/xen/xen-bus.c +++ b/hw/xen/xen-bus.c @@ -846,8 +846,11 @@ void xen_device_set_event_channel_context(XenDevice *xendev, NULL, NULL, NULL, NULL, NULL); channel->ctx = ctx; - aio_set_fd_handler(channel->ctx, qemu_xen_evtchn_fd(channel->xeh), true, - xen_device_event, NULL, xen_device_poll, NULL, channel); + if (ctx) { + aio_set_fd_handler(channel->ctx, qemu_xen_evtchn_fd(channel->xeh), + true, xen_device_event, NULL, xen_device_poll, NULL, + channel); + } } XenEventChannel *xen_device_bind_event_channel(XenDevice *xendev,