On 07/26/2018 09:54 PM, Christian Borntraeger wrote: > From: Tony Krowiak <akrowiak@xxxxxxxxxxxxx> > > Introduces ioctl access to the VFIO AP Matrix device driver > by implementing the VFIO_DEVICE_GET_INFO ioctl. This ioctl > provides the VFIO AP Matrix device driver information to the > guest machine. > > Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx> > Reviewed-by: Pierre Morel <pmorel@xxxxxxxxxxxxx> > Acked-by: Halil Pasic <pasic@xxxxxxxxxxxxx> > Tested-by: Michael Mueller <mimu@xxxxxxxxxxxxx> > Tested-by: Farhan Ali <alifm@xxxxxxxxxxxxx> > Tested-by: Pierre Morel <pmorel@xxxxxxxxxxxxx> > Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> > --- > drivers/s390/crypto/vfio_ap_ops.c | 43 +++++++++++++++++++++++++++++++ > 1 file changed, 43 insertions(+) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index d06067a23000..01c429cb51d5 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -867,6 +867,48 @@ static void vfio_ap_mdev_release(struct mdev_device *mdev) > module_put(THIS_MODULE); > } > > +static int vfio_ap_mdev_get_device_info(unsigned long arg) > +{ > + unsigned long minsz; > + struct vfio_device_info info; > + > + minsz = offsetofend(struct vfio_device_info, num_irqs); > + > + if (copy_from_user(&info, (void __user *)arg, minsz)) > + return -EFAULT; > + > + if (info.argsz < minsz) { > + pr_warn("%s: Argument size %u less than min size %li\n", > + VFIO_AP_MODULE_NAME, info.argsz, minsz); Do you really need this pr_warn here? The -EINVAL should give a clear indication about the problem already. (and in the worst case, a malicious userspace program could use it to flood the kernel log) > + return -EINVAL; > + } > + > + info.flags = VFIO_DEVICE_FLAGS_AP; > + info.num_regions = 0; > + info.num_irqs = 0; > + > + return copy_to_user((void __user *)arg, &info, minsz); > +} > + > +static ssize_t vfio_ap_mdev_ioctl(struct mdev_device *mdev, > + unsigned int cmd, unsigned long arg) > +{ > + int ret; > + > + switch (cmd) { > + case VFIO_DEVICE_GET_INFO: > + ret = vfio_ap_mdev_get_device_info(arg); > + break; > + default: > + pr_warn("%s: ioctl command %d is not a supported command\n", > + VFIO_AP_MODULE_NAME, cmd); I'd also remove this pr_warn - the -EOPNOTSUPP should be enough. > + ret = -EOPNOTSUPP; > + break; "break;" is also not required here. > + } > + > + return ret; > +} > + > static const struct mdev_parent_ops vfio_ap_matrix_ops = { > .owner = THIS_MODULE, > .supported_type_groups = vfio_ap_mdev_type_groups, > @@ -875,6 +917,7 @@ static const struct mdev_parent_ops vfio_ap_matrix_ops = { > .remove = vfio_ap_mdev_remove, > .open = vfio_ap_mdev_open, > .release = vfio_ap_mdev_release, > + .ioctl = vfio_ap_mdev_ioctl, > }; > > int vfio_ap_mdev_register(void) > Thomas -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html