From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40708) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XUuWi-0004kw-FJ for qemu-devel@nongnu.org; Fri, 19 Sep 2014 05:31:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XUuWZ-0004Zw-2Z for qemu-devel@nongnu.org; Fri, 19 Sep 2014 05:30:52 -0400 Received: from mail-wi0-x231.google.com ([2a00:1450:400c:c05::231]:64776) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XUuWY-0004ZO-JH for qemu-devel@nongnu.org; Fri, 19 Sep 2014 05:30:42 -0400 Received: by mail-wi0-f177.google.com with SMTP id em10so2628548wid.16 for ; Fri, 19 Sep 2014 02:30:36 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <541BF7B5.6080509@redhat.com> Date: Fri, 19 Sep 2014 11:30:29 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1407303308-4615-1-git-send-email-famz@redhat.com> <1407303308-4615-11-git-send-email-famz@redhat.com> In-Reply-To: <1407303308-4615-11-git-send-email-famz@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [RFC PATCH v2 10/10] virtio-scsi: Hook up with dataplane List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Fam Zheng , qemu-devel@nongnu.org Cc: kwolf@redhat.com, stefanha@redhat.com Il 06/08/2014 07:35, Fam Zheng ha scritto: > This enables the virtio-scsi-dataplane code by setting the iothread > in virtio-scsi device, and makes any function that is called by > back from dataplane to cooperate with the caller: they need to be > vring/iothread aware when handling the requests and using scsi devices > on the bus. > > Signed-off-by: Fam Zheng > --- > hw/scsi/virtio-scsi.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 71 insertions(+), 3 deletions(-) > > diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c > index 9e78e21..1f2a9b6 100644 > --- a/hw/scsi/virtio-scsi.c > +++ b/hw/scsi/virtio-scsi.c > @@ -62,6 +62,22 @@ void virtio_scsi_free_req(VirtIOSCSIReq *req) > g_free(req); > } > > +static void virtio_scsi_aio_acquire(VirtIOSCSICommon *vs) > +{ > + if (vs->dataplane_started) { > + assert(vs->ctx); > + aio_context_acquire(vs->ctx); > + } > +} > + > +static void virtio_scsi_aio_release(VirtIOSCSICommon *vs) > +{ > + if (vs->dataplane_started) { > + assert(vs->ctx); > + aio_context_release(vs->ctx); > + } > +} These are not needed if you do the acquire/release in virtio_scsi_push_event. > static void virtio_scsi_complete_req(VirtIOSCSIReq *req) > { > VirtIOSCSI *s = req->dev; > @@ -69,13 +85,19 @@ static void virtio_scsi_complete_req(VirtIOSCSIReq *req) > VirtIODevice *vdev = VIRTIO_DEVICE(s); > > qemu_iovec_from_buf(&req->resp_iov, 0, &req->resp, req->resp_size); > - virtqueue_push(vq, &req->elem, req->qsgl.size + req->resp_iov.size); > + if (req->vring) { > + assert(req->vq == NULL); > + virtio_scsi_vring_push_notify(req); > + } else { > + virtqueue_push(vq, &req->elem, req->qsgl.size + req->resp_iov.size); > + virtio_notify(vdev, vq); > + } > + > if (req->sreq) { > req->sreq->hba_private = NULL; > scsi_req_unref(req->sreq); > } > virtio_scsi_free_req(req); > - virtio_notify(vdev, vq); > } > > static void virtio_scsi_bad_req(void) > @@ -204,10 +226,16 @@ static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq) > static void virtio_scsi_do_tmf(VirtIOSCSI *s, VirtIOSCSIReq *req) > { > SCSIDevice *d = virtio_scsi_device_find(s, req->req.tmf.lun); > + VirtIOSCSICommon *vs = (VirtIOSCSICommon *)s; > SCSIRequest *r, *next; > BusChild *kid; > int target; > > + if (vs->dataplane_started && bdrv_get_aio_context(d->conf.bs) != vs->ctx) { > + aio_context_acquire(vs->ctx); > + bdrv_set_aio_context(d->conf.bs, vs->ctx); > + aio_context_release(vs->ctx); > + } > /* Here VIRTIO_SCSI_S_OK means "FUNCTION COMPLETE". */ > req->resp.tmf.response = VIRTIO_SCSI_S_OK; > > @@ -344,8 +372,13 @@ void virtio_scsi_handle_ctrl_req(VirtIOSCSI *s, VirtIOSCSIReq *req) > static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > { > VirtIOSCSI *s = (VirtIOSCSI *)vdev; > + VirtIOSCSICommon *vs = (VirtIOSCSICommon *)vdev; > VirtIOSCSIReq *req; > > + if (vs->ctx) { > + virtio_scsi_dataplane_start(vs); > + return; > + } > while ((req = virtio_scsi_pop_req(s, vq))) { > virtio_scsi_handle_ctrl_req(s, req); > } > @@ -439,6 +472,11 @@ void virtio_scsi_handle_cmd_req(VirtIOSCSI *s, VirtIOSCSIReq *req) > virtio_scsi_complete_cmd_req(req); > return; > } > + if (vs->dataplane_started && bdrv_get_aio_context(d->conf.bs) != vs->ctx) { > + aio_context_acquire(vs->ctx); > + bdrv_set_aio_context(d->conf.bs, vs->ctx); > + aio_context_release(vs->ctx); > + } > req->sreq = scsi_req_new(d, req->req.cmd.tag, > virtio_scsi_get_lun(req->req.cmd.lun), > req->req.cdb, req); > @@ -461,8 +499,13 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq) > { > /* use non-QOM casts in the data path */ > VirtIOSCSI *s = (VirtIOSCSI *)vdev; > + VirtIOSCSICommon *vs = (VirtIOSCSICommon *)vdev; > VirtIOSCSIReq *req; > > + if (vs->ctx) { > + virtio_scsi_dataplane_start(vs); > + return; > + } A migration state change notifier (like in virtio-blk-dataplane) is missing. > while ((req = virtio_scsi_pop_req(s, vq))) { > virtio_scsi_handle_cmd_req(s, req); > } > @@ -513,6 +556,9 @@ static void virtio_scsi_reset(VirtIODevice *vdev) > VirtIOSCSI *s = VIRTIO_SCSI(vdev); > VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); > > + if (vs->ctx) { > + virtio_scsi_dataplane_stop(vs); > + } > s->resetting++; > qbus_reset_all(&s->bus.qbus); > s->resetting--; > @@ -555,7 +601,11 @@ void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev, > return; > } > > - req = virtio_scsi_pop_req(s, vs->event_vq); > + if (vs->dataplane_started) { > + req = virtio_scsi_pop_req_vring(s, vs->event_vring); > + } else { > + req = virtio_scsi_pop_req(s, vs->event_vq); > + } > if (!req) { > s->events_dropped = true; > return; > @@ -592,7 +642,12 @@ void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev, > static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq) > { > VirtIOSCSI *s = VIRTIO_SCSI(vdev); > + VirtIOSCSICommon *vs = (VirtIOSCSICommon *)vdev; > > + if (vs->ctx) { > + virtio_scsi_dataplane_start(vs); > + return; > + } > if (s->events_dropped) { > virtio_scsi_push_event(s, NULL, VIRTIO_SCSI_T_NO_EVENT, 0); > } > @@ -602,11 +657,14 @@ static void virtio_scsi_change(SCSIBus *bus, SCSIDevice *dev, SCSISense sense) > { > VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus); > VirtIODevice *vdev = VIRTIO_DEVICE(s); > + VirtIOSCSICommon *vs = (VirtIOSCSICommon *)vdev; > > if (((vdev->guest_features >> VIRTIO_SCSI_F_CHANGE) & 1) && > dev->type != TYPE_ROM) { > + virtio_scsi_aio_acquire(vs); > virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_PARAM_CHANGE, > sense.asc | (sense.ascq << 8)); > + virtio_scsi_aio_release(vs); > } > } > > @@ -614,10 +672,13 @@ static void virtio_scsi_hotplug(SCSIBus *bus, SCSIDevice *dev) > { > VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus); > VirtIODevice *vdev = VIRTIO_DEVICE(s); > + VirtIOSCSICommon *vs = (VirtIOSCSICommon *)vdev; > > if ((vdev->guest_features >> VIRTIO_SCSI_F_HOTPLUG) & 1) { > + virtio_scsi_aio_acquire(vs); > virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_TRANSPORT_RESET, > VIRTIO_SCSI_EVT_RESET_RESCAN); > + virtio_scsi_aio_release(vs); > } > } > > @@ -625,10 +686,13 @@ static void virtio_scsi_hot_unplug(SCSIBus *bus, SCSIDevice *dev) > { > VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus); > VirtIODevice *vdev = VIRTIO_DEVICE(s); > + VirtIOSCSICommon *vs = (VirtIOSCSICommon *)vdev; > > if ((vdev->guest_features >> VIRTIO_SCSI_F_HOTPLUG) & 1) { > + virtio_scsi_aio_acquire(vs); > virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_TRANSPORT_RESET, > VIRTIO_SCSI_EVT_RESET_REMOVED); > + virtio_scsi_aio_release(vs); > } > } > > @@ -671,6 +735,10 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp, > s->cmd_vqs[i] = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE, > cmd); > } > + > + if (s->conf.iothread) { > + virtio_scsi_set_iothread(s, s->conf.iothread); > + } > } > > static void virtio_scsi_device_realize(DeviceState *dev, Error **errp) >