* Auger Eric <eric.au...@redhat.com> [2017-05-01 19:28:23 +0200]:
Hi Eric,
> > diff --git a/hw/s390x/s390-ccw.h b/hw/s390x/s390-ccw.h
> > index b58d8e9..4e2fa65 100644
> > --- a/hw/s390x/s390-ccw.h
> > +++ b/hw/s390x/s390-ccw.h
> > @@ -27,6 +27,7 @@ typedef struct S390CCWDevice {
> > CcwDevice parent_obj;
> > CssDevId hostid;
> > char *mdevid;
> > + int (*handle_request) (ORB *, SCSW *, void *);
> shouldn't this callback be part of the class instead?
Ok. This sounds more proper.
>
> > } S390CCWDevice;
> >
> > typedef struct S390CCWDeviceClass {
> > diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c
> > index cda3057..3ff78c5 100644
> > --- a/hw/vfio/ccw.c
> > +++ b/hw/vfio/ccw.c
> > @@ -47,6 +47,36 @@ struct VFIODeviceOps vfio_ccw_ops = {
> > .vfio_compute_needs_reset = vfio_ccw_compute_needs_reset,
> > };
> >
> > +static int vfio_ccw_handle_request(ORB *orb, SCSW *scsw, void *data)
> > +{
> > + S390CCWDevice *cdev = data;
> > + VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
> > + struct ccw_io_region *region = vcdev->io_region;
> > + int ret;
> > +
> > + QEMU_BUILD_BUG_ON(sizeof(region->orb_area) != sizeof(ORB));
> > + QEMU_BUILD_BUG_ON(sizeof(region->scsw_area) != sizeof(SCSW));
> > + QEMU_BUILD_BUG_ON(sizeof(region->irb_area) != sizeof(IRB));
> > +
> > + memset(region, 0, sizeof(*region));
> > +
> > + memcpy(region->orb_area, orb, sizeof(ORB));
> > + memcpy(region->scsw_area, scsw, sizeof(SCSW));
> > +
> > +again:
> > + ret = pwrite(vcdev->vdev.fd, region,
> > + vcdev->io_region_size, vcdev->io_region_offset);
> > + if (ret != vcdev->io_region_size) {
> > + if (errno == EAGAIN) {
> > + goto again;
> > + }
> > + error_report("vfio-ccw: wirte I/O region failed with errno=%d",
> > errno);
> > + return -errno;
> > + }
> > +
> > + return region->ret_code;
> > +}
> > +
> > static void vfio_ccw_reset(DeviceState *dev)
> > {
> > CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev);
> > @@ -59,10 +89,52 @@ static void vfio_ccw_reset(DeviceState *dev)
> > static void vfio_ccw_io_notifier_handler(void *opaque)
> > {
> > VFIOCCWDevice *vcdev = opaque;
> > + struct ccw_io_region *region = vcdev->io_region;
> > + S390CCWDevice *cdev = S390_CCW_DEVICE(vcdev);
> > + CcwDevice *ccw_dev = CCW_DEVICE(cdev);
> > + SubchDev *sch = ccw_dev->sch;
> > + SCSW *s = &sch->curr_status.scsw;
> > + IRB irb;
> >
> > if (!event_notifier_test_and_clear(&vcdev->io_notifier)) {
> > return;
> > }
> > +
> > + if (pread(vcdev->vdev.fd, region,
> > + vcdev->io_region_size, vcdev->io_region_offset) == -1) {
> is it possible to read less bytes than requested?
Currently, impossible. The kernel side returns either the full region,
or an error.
But we surely could make it more friendly for a partial return. I will
add a check for that case, and generate a channel program check for it.
>
> Thanks
>
> Eric
> > + switch (errno) {
> > + case ENODEV:
> > + /* Generate a deferred cc 3 condition. */
> > + s->flags |= SCSW_FLAGS_MASK_CC;
> > + s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
> > + s->ctrl |= (SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND);
> > + goto read_err;
> > + case EFAULT:
> > + /* memory problem, generate channel data check */
> > + s->ctrl &= ~SCSW_ACTL_START_PEND;
> > + s->cstat = SCSW_CSTAT_DATA_CHECK;
> > + s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
> > + s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
> > + SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
> > + goto read_err;
> > + default:
> > + /* error, generate channel program check */
> > + s->ctrl &= ~SCSW_ACTL_START_PEND;
> > + s->cstat = SCSW_CSTAT_PROG_CHECK;
> > + s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
> > + s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
> > + SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
> > + goto read_err;
> > + }
> > + }
> > +
> > + memcpy(&irb, region->irb_area, sizeof(IRB));
> > +
> > + /* Update control block via irb. */
> > + copy_scsw_to_guest(s, &irb.scsw);
> > +
> > +read_err:
> > + css_inject_io_interrupt(sch);
> > }
> >
> > static void vfio_ccw_register_io_notifier(VFIOCCWDevice *vcdev, Error
> > **errp)
[...]
--
Dong Jia Shi
