From ad07cd69ecaffbaa015459a46975ab32e50df805 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Fri, 21 Oct 2016 22:48:10 +0200 Subject: virtio-scsi: always use dataplane path if ioeventfd is active Override start_ioeventfd and stop_ioeventfd to start/stop the whole dataplane logic. This has some positive side effects: - no need anymore for virtio_add_queue_aio (i.e. a revert of commit 1c627137c10ee2dcf59e0383ade8a9abfa2d4355) - no need anymore to switch from generic ioeventfd handlers to dataplane It detects some errors better: $ qemu-system-x86_64 -object iothread,id=io \ -device virtio-scsi-pci,ioeventfd=off,iothread=io qemu-system-x86_64: -device virtio-scsi-pci,ioeventfd=off,iothread=io: ioeventfd is required for iothread while previously it would have started just fine. Reviewed-by: Cornelia Huck Signed-off-by: Paolo Bonzini Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/scsi/virtio-scsi-dataplane.c | 56 +++++++++++++++++++++++++---------------- hw/scsi/virtio-scsi.c | 24 ++++++++---------- 2 files changed, 45 insertions(+), 35 deletions(-) (limited to 'hw/scsi') diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplane.c index f537b4e900..aa6be541ec 100644 --- a/hw/scsi/virtio-scsi-dataplane.c +++ b/hw/scsi/virtio-scsi-dataplane.c @@ -12,6 +12,7 @@ */ #include "qemu/osdep.h" +#include "qapi/error.h" #include "hw/virtio/virtio-scsi.h" #include "qemu/error-report.h" #include "sysemu/block-backend.h" @@ -21,20 +22,30 @@ #include "hw/virtio/virtio-access.h" /* Context: QEMU global mutex held */ -void virtio_scsi_set_iothread(VirtIOSCSI *s, IOThread *iothread) +void virtio_scsi_dataplane_setup(VirtIOSCSI *s, Error **errp) { - BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s))); - VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); + VirtIODevice *vdev = VIRTIO_DEVICE(s); + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); - assert(!s->ctx); - s->ctx = iothread_get_aio_context(vs->conf.iothread); - - /* Don't try if transport does not support notifiers. */ - if (!k->set_guest_notifiers || !k->ioeventfd_assign) { - fprintf(stderr, "virtio-scsi: Failed to set iothread " - "(transport does not support notifiers)"); - exit(1); + if (vs->conf.iothread) { + if (!k->set_guest_notifiers || !k->ioeventfd_assign) { + error_setg(errp, + "device is incompatible with iothread " + "(transport does not support notifiers)"); + return; + } + if (!virtio_device_ioeventfd_enabled(vdev)) { + error_setg(errp, "ioeventfd is required for iothread"); + return; + } + s->ctx = iothread_get_aio_context(vs->conf.iothread); + } else { + if (!virtio_device_ioeventfd_enabled(vdev)) { + return; + } + s->ctx = qemu_get_aio_context(); } } @@ -105,19 +116,19 @@ static void virtio_scsi_clear_aio(VirtIOSCSI *s) } /* Context: QEMU global mutex held */ -void virtio_scsi_dataplane_start(VirtIOSCSI *s) +int virtio_scsi_dataplane_start(VirtIODevice *vdev) { int i; int rc; - BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s))); + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); - VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); + VirtIOSCSI *s = VIRTIO_SCSI(vdev); if (s->dataplane_started || s->dataplane_starting || - s->dataplane_fenced || - s->ctx != iothread_get_aio_context(vs->conf.iothread)) { - return; + s->dataplane_fenced) { + return 0; } s->dataplane_starting = true; @@ -152,7 +163,7 @@ void virtio_scsi_dataplane_start(VirtIOSCSI *s) s->dataplane_starting = false; s->dataplane_started = true; aio_context_release(s->ctx); - return; + return 0; fail_vrings: virtio_scsi_clear_aio(s); @@ -165,14 +176,16 @@ fail_guest_notifiers: s->dataplane_fenced = true; s->dataplane_starting = false; s->dataplane_started = true; + return -ENOSYS; } /* Context: QEMU global mutex held */ -void virtio_scsi_dataplane_stop(VirtIOSCSI *s) +void virtio_scsi_dataplane_stop(VirtIODevice *vdev) { - BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s))); + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); - VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); + VirtIOSCSI *s = VIRTIO_SCSI(vdev); int i; if (!s->dataplane_started || s->dataplane_stopping) { @@ -186,7 +199,6 @@ void virtio_scsi_dataplane_stop(VirtIOSCSI *s) return; } s->dataplane_stopping = true; - assert(s->ctx == iothread_get_aio_context(vs->conf.iothread)); aio_context_acquire(s->ctx); diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c index 4762f05274..3e5ae6ac0f 100644 --- a/hw/scsi/virtio-scsi.c +++ b/hw/scsi/virtio-scsi.c @@ -434,7 +434,7 @@ static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) VirtIOSCSI *s = (VirtIOSCSI *)vdev; if (s->ctx) { - virtio_scsi_dataplane_start(s); + virtio_device_start_ioeventfd(vdev); if (!s->dataplane_fenced) { return; } @@ -610,7 +610,7 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq) VirtIOSCSI *s = (VirtIOSCSI *)vdev; if (s->ctx) { - virtio_scsi_dataplane_start(s); + virtio_device_start_ioeventfd(vdev); if (!s->dataplane_fenced) { return; } @@ -669,9 +669,7 @@ static void virtio_scsi_reset(VirtIODevice *vdev) VirtIOSCSI *s = VIRTIO_SCSI(vdev); VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); - if (s->ctx) { - virtio_scsi_dataplane_stop(s); - } + assert(!s->dataplane_started); s->resetting++; qbus_reset_all(&s->bus.qbus); s->resetting--; @@ -749,7 +747,7 @@ static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq) VirtIOSCSI *s = VIRTIO_SCSI(vdev); if (s->ctx) { - virtio_scsi_dataplane_start(s); + virtio_device_start_ioeventfd(vdev); if (!s->dataplane_fenced) { return; } @@ -848,14 +846,10 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp, s->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE; s->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE; - s->ctrl_vq = virtio_add_queue_aio(vdev, VIRTIO_SCSI_VQ_SIZE, ctrl); - s->event_vq = virtio_add_queue_aio(vdev, VIRTIO_SCSI_VQ_SIZE, evt); + s->ctrl_vq = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE, ctrl); + s->event_vq = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE, evt); for (i = 0; i < s->conf.num_queues; i++) { - s->cmd_vqs[i] = virtio_add_queue_aio(vdev, VIRTIO_SCSI_VQ_SIZE, cmd); - } - - if (s->conf.iothread) { - virtio_scsi_set_iothread(VIRTIO_SCSI(s), s->conf.iothread); + s->cmd_vqs[i] = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE, cmd); } } @@ -885,6 +879,8 @@ static void virtio_scsi_device_realize(DeviceState *dev, Error **errp) return; } } + + virtio_scsi_dataplane_setup(s, errp); } static void virtio_scsi_instance_init(Object *obj) @@ -957,6 +953,8 @@ static void virtio_scsi_class_init(ObjectClass *klass, void *data) vdc->set_config = virtio_scsi_set_config; vdc->get_features = virtio_scsi_get_features; vdc->reset = virtio_scsi_reset; + vdc->start_ioeventfd = virtio_scsi_dataplane_start; + vdc->stop_ioeventfd = virtio_scsi_dataplane_stop; hc->plug = virtio_scsi_hotplug; hc->unplug = virtio_scsi_hotunplug; } -- cgit v1.2.3