diff options
Diffstat (limited to 'hw/scsi/virtio-scsi.c')
| -rw-r--r-- | hw/scsi/virtio-scsi.c | 80 |
1 files changed, 41 insertions, 39 deletions
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c index 9c751bf296..ca365a70e9 100644 --- a/hw/scsi/virtio-scsi.c +++ b/hw/scsi/virtio-scsi.c @@ -123,6 +123,30 @@ static void virtio_scsi_complete_req(VirtIOSCSIReq *req) virtio_scsi_free_req(req); } +static void virtio_scsi_complete_req_bh(void *opaque) +{ + VirtIOSCSIReq *req = opaque; + + virtio_scsi_complete_req(req); +} + +/* + * Called from virtio_scsi_do_one_tmf_bh() in main loop thread. The main loop + * thread cannot touch the virtqueue since that could race with an IOThread. + */ +static void virtio_scsi_complete_req_from_main_loop(VirtIOSCSIReq *req) +{ + VirtIOSCSI *s = req->dev; + + if (!s->ctx || s->ctx == qemu_get_aio_context()) { + /* No need to schedule a BH when there is no IOThread */ + virtio_scsi_complete_req(req); + } else { + /* Run request completion in the IOThread */ + aio_wait_bh_oneshot(s->ctx, virtio_scsi_complete_req_bh, req); + } +} + static void virtio_scsi_bad_req(VirtIOSCSIReq *req) { virtio_error(VIRTIO_DEVICE(req->dev), "wrong size for virtio-scsi headers"); @@ -338,10 +362,7 @@ static void virtio_scsi_do_one_tmf_bh(VirtIOSCSIReq *req) out: object_unref(OBJECT(d)); - - virtio_scsi_acquire(s); - virtio_scsi_complete_req(req); - virtio_scsi_release(s); + virtio_scsi_complete_req_from_main_loop(req); } /* Some TMFs must be processed from the main loop thread */ @@ -354,18 +375,16 @@ static void virtio_scsi_do_tmf_bh(void *opaque) GLOBAL_STATE_CODE(); - virtio_scsi_acquire(s); + WITH_QEMU_LOCK_GUARD(&s->tmf_bh_lock) { + QTAILQ_FOREACH_SAFE(req, &s->tmf_bh_list, next, tmp) { + QTAILQ_REMOVE(&s->tmf_bh_list, req, next); + QTAILQ_INSERT_TAIL(&reqs, req, next); + } - QTAILQ_FOREACH_SAFE(req, &s->tmf_bh_list, next, tmp) { - QTAILQ_REMOVE(&s->tmf_bh_list, req, next); - QTAILQ_INSERT_TAIL(&reqs, req, next); + qemu_bh_delete(s->tmf_bh); + s->tmf_bh = NULL; } - qemu_bh_delete(s->tmf_bh); - s->tmf_bh = NULL; - - virtio_scsi_release(s); - QTAILQ_FOREACH_SAFE(req, &reqs, next, tmp) { QTAILQ_REMOVE(&reqs, req, next); virtio_scsi_do_one_tmf_bh(req); @@ -379,8 +398,7 @@ static void virtio_scsi_reset_tmf_bh(VirtIOSCSI *s) GLOBAL_STATE_CODE(); - virtio_scsi_acquire(s); - + /* Called after ioeventfd has been stopped, so tmf_bh_lock is not needed */ if (s->tmf_bh) { qemu_bh_delete(s->tmf_bh); s->tmf_bh = NULL; @@ -393,19 +411,19 @@ static void virtio_scsi_reset_tmf_bh(VirtIOSCSI *s) req->resp.tmf.response = VIRTIO_SCSI_S_TARGET_FAILURE; virtio_scsi_complete_req(req); } - - virtio_scsi_release(s); } static void virtio_scsi_defer_tmf_to_bh(VirtIOSCSIReq *req) { VirtIOSCSI *s = req->dev; - QTAILQ_INSERT_TAIL(&s->tmf_bh_list, req, next); + WITH_QEMU_LOCK_GUARD(&s->tmf_bh_lock) { + QTAILQ_INSERT_TAIL(&s->tmf_bh_list, req, next); - if (!s->tmf_bh) { - s->tmf_bh = qemu_bh_new(virtio_scsi_do_tmf_bh, s); - qemu_bh_schedule(s->tmf_bh); + if (!s->tmf_bh) { + s->tmf_bh = qemu_bh_new(virtio_scsi_do_tmf_bh, s); + qemu_bh_schedule(s->tmf_bh); + } } } @@ -624,9 +642,7 @@ static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) return; } - virtio_scsi_acquire(s); virtio_scsi_handle_ctrl_vq(s, vq); - virtio_scsi_release(s); } static void virtio_scsi_complete_cmd_req(VirtIOSCSIReq *req) @@ -864,9 +880,7 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq) return; } - virtio_scsi_acquire(s); virtio_scsi_handle_cmd_vq(s, vq); - virtio_scsi_release(s); } static void virtio_scsi_get_config(VirtIODevice *vdev, @@ -1013,9 +1027,7 @@ static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq) return; } - virtio_scsi_acquire(s); virtio_scsi_handle_event_vq(s, vq); - virtio_scsi_release(s); } static void virtio_scsi_change(SCSIBus *bus, SCSIDevice *dev, SCSISense sense) @@ -1034,9 +1046,7 @@ static void virtio_scsi_change(SCSIBus *bus, SCSIDevice *dev, SCSISense sense) }, }; - virtio_scsi_acquire(s); virtio_scsi_push_event(s, &info); - virtio_scsi_release(s); } } @@ -1053,17 +1063,13 @@ static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev, VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev); VirtIOSCSI *s = VIRTIO_SCSI(vdev); SCSIDevice *sd = SCSI_DEVICE(dev); - AioContext *old_context; int ret; if (s->ctx && !s->dataplane_fenced) { if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) { return; } - old_context = blk_get_aio_context(sd->conf.blk); - aio_context_acquire(old_context); ret = blk_set_aio_context(sd->conf.blk, s->ctx, errp); - aio_context_release(old_context); if (ret < 0) { return; } @@ -1079,10 +1085,8 @@ static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev, }, }; - virtio_scsi_acquire(s); virtio_scsi_push_event(s, &info); scsi_bus_set_ua(&s->bus, SENSE_CODE(REPORTED_LUNS_CHANGED)); - virtio_scsi_release(s); } } @@ -1104,17 +1108,13 @@ static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev, qdev_simple_device_unplug_cb(hotplug_dev, dev, errp); if (s->ctx) { - virtio_scsi_acquire(s); /* If other users keep the BlockBackend in the iothread, that's ok */ blk_set_aio_context(sd->conf.blk, qemu_get_aio_context(), NULL); - virtio_scsi_release(s); } if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) { - virtio_scsi_acquire(s); virtio_scsi_push_event(s, &info); scsi_bus_set_ua(&s->bus, SENSE_CODE(REPORTED_LUNS_CHANGED)); - virtio_scsi_release(s); } } @@ -1235,6 +1235,7 @@ static void virtio_scsi_device_realize(DeviceState *dev, Error **errp) Error *err = NULL; QTAILQ_INIT(&s->tmf_bh_list); + qemu_mutex_init(&s->tmf_bh_lock); virtio_scsi_common_realize(dev, virtio_scsi_handle_ctrl, @@ -1277,6 +1278,7 @@ static void virtio_scsi_device_unrealize(DeviceState *dev) qbus_set_hotplug_handler(BUS(&s->bus), NULL); virtio_scsi_common_unrealize(dev); + qemu_mutex_destroy(&s->tmf_bh_lock); } static Property virtio_scsi_properties[] = { |