Commit 24e58a7b authored by Jared Rossi's avatar Jared Rossi Committed by Cornelia Huck
Browse files

vfio-ccw: allow non-prefetch ORBs 



Remove the explicit prefetch check when using vfio-ccw devices.
This check does not trigger in practice as all Linux channel programs
are intended to use prefetch.

Newer Linux kernel versions do not require to force the PFCH flag with
vfio-ccw devices anymore.

Signed-off-by: default avatarJared Rossi <jrossi@linux.ibm.com>
Reviewed-by: default avatarEric Farman <farman@linux.ibm.com>
Message-Id: <20200512181535.18630-2-jrossi@linux.ibm.com>
Signed-off-by: default avatarCornelia Huck <cohuck@redhat.com>
parent 61a3d5ed

hw/vfio/ccw.c

+3 −10
Original line number Diff line number Diff line
@@ -74,17 +74,10 @@ static IOInstEnding vfio_ccw_handle_request(SubchDev *sch) 
    struct ccw_io_region *region = vcdev->io_region;

    int ret;



    if (!(sch->orb.ctrl0 & ORB_CTRL0_MASK_PFCH)) {

        if (!(vcdev->force_orb_pfch)) {

            warn_once_pfch(vcdev, sch, "requires PFCH flag set");

            sch_gen_unit_exception(sch);

            css_inject_io_interrupt(sch);

            return IOINST_CC_EXPECTED;

        } else {

    if (!(sch->orb.ctrl0 & ORB_CTRL0_MASK_PFCH) && vcdev->force_orb_pfch) {

        sch->orb.ctrl0 |= ORB_CTRL0_MASK_PFCH;

        warn_once_pfch(vcdev, sch, "PFCH flag forced");

    }

    }



    QEMU_BUILD_BUG_ON(sizeof(region->orb_area) != sizeof(ORB));

    QEMU_BUILD_BUG_ON(sizeof(region->scsw_area) != sizeof(SCSW));