Re: [Qemu-devel] [PATCH v6 08/13] vfio/ccw: get io region info

[Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>]

* Auger Eric <eric.auger@redhat.com> [2017-05-01 13:08:24 +0200]:

> Hi,
> 
> On 28/04/2017 15:09, Dong Jia Shi wrote:
> > vfio-ccw provides an MMIO region for I/O operations. We fetch its
> > information via ioctls here, then we can use it performing I/O
> > instructions and retrieving I/O results later on.
> > 
> > Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
> > ---
> >  hw/vfio/ccw.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 52 insertions(+)
> > 
> > diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c
> > index cd4dfe8..a285b23 100644
> > --- a/hw/vfio/ccw.c
> > +++ b/hw/vfio/ccw.c
> > @@ -12,6 +12,7 @@
> >   */
> >  
> >  #include <linux/vfio.h>
> > +#include <linux/vfio_ccw.h>
> >  #include <sys/ioctl.h>
> >  
> >  #include "qemu/osdep.h"
> > @@ -26,6 +27,9 @@
> >  typedef struct VFIOCCWDevice {
> >      S390CCWDevice cdev;
> >      VFIODevice vdev;
> > +    uint64_t io_region_size;
> > +    uint64_t io_region_offset;
> > +    struct ccw_io_region *io_region;
> >  } VFIOCCWDevice;
> >  
> >  static void vfio_ccw_compute_needs_reset(VFIODevice *vdev)
> > @@ -50,6 +54,46 @@ static void vfio_ccw_reset(DeviceState *dev)
> >      ioctl(vcdev->vdev.fd, VFIO_DEVICE_RESET);
> >  }
> >  
> > +static void vfio_ccw_get_region(VFIOCCWDevice *vcdev, Error **errp)
> > +{
> > +    VFIODevice *vdev = &vcdev->vdev;
> > +    struct vfio_region_info *info;
> > +    int ret;
> > +
> > +    /* Sanity check device */
> > +    if (!(vdev->flags & VFIO_DEVICE_FLAGS_CCW)) {
> > +        error_setg(errp, "vfio: Um, this isn't a vfio-ccw device");
> > +        return;
> > +    }
> > +
> > +    if (vdev->num_regions < VFIO_CCW_CONFIG_REGION_INDEX + 1) {
> > +        error_setg(errp, "vfio: Unexpected number of the I/O region %u",
> > +                   vdev->num_regions);
> > +        return;
> > +    }
> > +
> > +    ret = vfio_get_region_info(vdev, VFIO_CCW_CONFIG_REGION_INDEX, &info);
> > +    if (ret) {
> > +        error_setg(errp, "vfio: Error getting config info: %d", ret);
> > +        return;
> > +    }
> > +
> > +    vcdev->io_region_size = info->size;
> > +    if (sizeof(*vcdev->io_region) != vcdev->io_region_size) {
> > +        error_setg(errp, "vfio: Unexpected size of the I/O region");
> g_free(info)
Good catch!

> > +        return;
> > +    }
> > +    vcdev->io_region_offset = info->offset;
> > +    vcdev->io_region = g_malloc0(info->size);
> > +
> > +    g_free(info);
> > +}
> > +
> > +static void vfio_ccw_put_region(VFIOCCWDevice *vcdev)
> > +{
> > +    g_free(vcdev->io_region);
> > +}
> > +
> >  static void vfio_put_device(VFIOCCWDevice *vcdev)
> >  {
> >      g_free(vcdev->vdev.name);
> > @@ -126,8 +170,15 @@ static void vfio_ccw_realize(DeviceState *dev, Error **errp)
> >          goto out_device_err;
> >      }
> >  
> > +    vfio_ccw_get_region(vcdev, errp);
> > +    if (*errp) {
> local err?
As replied on the previous thread, ok.

> 
> Thanks
> 
> Eric
> > +        goto out_region_err;
> > +    }
> > +
> >      return;
> >  
> > +out_region_err:
> > +    vfio_put_device(vcdev);
> >  out_device_err:
> >      vfio_ccw_put_group(group);
> >  out_group_err:
> > @@ -144,6 +195,7 @@ static void vfio_ccw_unrealize(DeviceState *dev, Error **errp)
> >      S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(cdev);
> >      VFIOGroup *group = vcdev->vdev.group;
> >  
> > +    vfio_ccw_put_region(vcdev);
> >      vfio_put_device(vcdev);
> >      vfio_put_group(group);
> >  
> > 
> 

-- 
Dong Jia Shi