[src/trunk]: src/sys/dev/pci several small tweaks:

[jdolecek <jdolecek%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/a72e74d7e482
branches:  trunk
changeset: 822312:a72e74d7e482
user:      jdolecek <jdolecek%NetBSD.org@localhost>
date:      Mon Mar 13 21:06:50 2017 +0000

description:
several small tweaks:
- use MSIX if available
- fix off-by-one for nluns/ntargets (code inspection, not actual effect)
- when virtio_enqueue_reserve() fails, do not execute vioscsi_req_put()
  and hence virtio_dequeue_commit() as there is nothing to commit, just
  unload the xs and return; also report XS_RESOURCE_SHORTAGE, it's
  semi-normal situation
- set status/resid in vioscsi_req_done() before the switch, so that
  the override for VIRTIO_SCSI_S_BAD_TARGET actually has effect
- g/c vioscsi_req_put(), call the appropriate cleanup routines directly
- stop initializing id/task_attr in vioscsi_req_get(), it's overwritten
  in vioscsi_scsipi_request() anyway

diffstat:

 sys/dev/pci/vioscsi.c |  51 +++++++++++++++++++++------------------------------
 1 files changed, 21 insertions(+), 30 deletions(-)

diffs (147 lines):

diff -r a27821ee45f5 -r a72e74d7e482 sys/dev/pci/vioscsi.c
--- a/sys/dev/pci/vioscsi.c     Mon Mar 13 20:47:38 2017 +0000
+++ b/sys/dev/pci/vioscsi.c     Mon Mar 13 21:06:50 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vioscsi.c,v 1.10 2017/03/13 20:47:38 jdolecek Exp $    */
+/*     $NetBSD: vioscsi.c,v 1.11 2017/03/13 21:06:50 jdolecek Exp $    */
 /*     $OpenBSD: vioscsi.c,v 1.3 2015/03/14 03:38:49 jsg Exp $ */
 
 /*
@@ -18,7 +18,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vioscsi.c,v 1.10 2017/03/13 20:47:38 jdolecek Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vioscsi.c,v 1.11 2017/03/13 21:06:50 jdolecek Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -85,7 +85,6 @@
 static void     vioscsi_req_done(struct vioscsi_softc *, struct virtio_softc *,
     struct vioscsi_req *);
 static struct vioscsi_req *vioscsi_req_get(struct vioscsi_softc *);
-static void     vioscsi_req_put(struct vioscsi_softc *, struct vioscsi_req *);
 
 static const char *const vioscsi_vq_names[] = {
        "control",
@@ -133,6 +132,8 @@
        vsc->sc_intrhand = virtio_vq_intr;
        vsc->sc_flags = 0;
 
+       vsc->sc_flags |= VIRTIO_F_PCI_INTR_MSIX;
+
        features = virtio_negotiate_features(vsc, 0);
        snprintb(buf, sizeof(buf), VIRTIO_COMMON_FLAG_BITS, features);
        aprint_normal(": Features: %s\n", buf);
@@ -193,8 +194,8 @@
        chan->chan_adapter = adapt;
        chan->chan_bustype = &scsi_bustype;
        chan->chan_channel = 0;
-       chan->chan_ntargets = max_target;
-       chan->chan_nluns = max_lun;
+       chan->chan_ntargets = max_target + 1;
+       chan->chan_nluns = max_lun + 1;
        chan->chan_id = 0;
        chan->chan_flags = SCSIPI_CHAN_NOSETTLE;
 
@@ -223,7 +224,7 @@
        struct scsipi_periph *periph;
        struct vioscsi_req *vr;
        struct virtio_scsi_req_hdr *req;
-       struct virtqueue *vq = &sc->sc_vqs[2];
+       struct virtqueue *vq = &sc->sc_vqs[VIOSCSI_VQ_REQUEST];
        int slot, error;
 
        DPRINTF(("%s: enter\n", __func__));
@@ -325,10 +326,10 @@
        default:
                aprint_error_dev(sc->sc_dev, "error %d loading DMA map\n",
                    error);
-       stuffup:
+stuffup:
                xs->error = XS_DRIVER_STUFFUP;
 nomore:
-               vioscsi_req_put(sc, vr);
+               /* nothing else to free */
                scsipi_done(xs);
                return;
        }
@@ -340,7 +341,9 @@
        error = virtio_enqueue_reserve(vsc, vq, slot, nsegs);
        if (error) {
                DPRINTF(("%s: error reserving %d\n", __func__, error));
-               goto stuffup;
+               bus_dmamap_unload(vsc->sc_dmat, vr->vr_data);
+               xs->error = XS_RESOURCE_SHORTAGE;
+               goto nomore;
        }
 
        bus_dmamap_sync(vsc->sc_dmat, vr->vr_control,
@@ -411,6 +414,9 @@
        bus_dmamap_sync(vsc->sc_dmat, vr->vr_data, 0, xs->datalen,
            XS2DMAPOST(xs));
 
+       xs->status = vr->vr_res.status;
+       xs->resid = vr->vr_res.residual;
+
        switch (vr->vr_res.response) {
        case VIRTIO_SCSI_S_OK:
                sense_len = MIN(sizeof(xs->sense), vr->vr_res.sense_len);
@@ -433,14 +439,12 @@
                break;
        }
 
-       xs->status = vr->vr_res.status;
-       xs->resid = vr->vr_res.residual;
-
        DPRINTF(("%s: done %d, %d, %d\n", __func__,
            xs->error, xs->status, xs->resid));
 
+       bus_dmamap_unload(vsc->sc_dmat, vr->vr_data);
        vr->vr_xs = NULL;
-       vioscsi_req_put(sc, vr);
+
        scsipi_done(xs);
 }
 
@@ -460,7 +464,11 @@
                        break;
 
                DPRINTF(("%s: slot=%d\n", __func__, slot));
+
                vioscsi_req_done(sc, vsc, &sc->sc_reqs[slot]);
+
+               virtio_dequeue_commit(vsc, vq, slot);
+
                ret = 1;
        }
 
@@ -484,28 +492,11 @@
        KASSERT(slot < sc->sc_nreqs);
        vr = &sc->sc_reqs[slot];
 
-       vr->vr_req.id = slot;
-       vr->vr_req.task_attr = VIRTIO_SCSI_S_SIMPLE;
-
        DPRINTF(("%s: %p, %d\n", __func__, vr, slot));
 
        return vr;
 }
 
-static void
-vioscsi_req_put(struct vioscsi_softc *sc, struct vioscsi_req *vr)
-{
-       struct virtio_softc *vsc = device_private(device_parent(sc->sc_dev));
-       struct virtqueue *vq = &sc->sc_vqs[2];
-       int slot = vr - sc->sc_reqs;
-
-       DPRINTF(("%s: %p, %d\n", __func__, vr, slot));
-
-       bus_dmamap_unload(vsc->sc_dmat, vr->vr_data);
-
-       virtio_dequeue_commit(vsc, vq, slot);
-}
-
 int
 vioscsi_alloc_reqs(struct vioscsi_softc *sc, struct virtio_softc *vsc,
     int qsize, uint32_t seg_max)