Re: [PATCH v2 3/3] vfio: ap: AP Queue Interrupt Control VFIO ioctl calls

[Pierre Morel]

On 29/11/2018 12:37, Cornelia Huck wrote:
> On Thu, 22 Nov 2018 18:11:15 +0100
> Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
>
> > This is the implementation of the VFIO ioctl calls to handle
> > the AQIC interception and use GISA to handle interrupts.
> >
> > Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> > ---
> >   drivers/s390/crypto/vfio_ap_ops.c | 110 +++++++++++++++++++++++++++++++++++++-
> >   1 file changed, 109 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> > index 272ef42..f6e942f 100644
> > --- a/drivers/s390/crypto/vfio_ap_ops.c
> > +++ b/drivers/s390/crypto/vfio_ap_ops.c
> > @@ -895,12 +895,121 @@ static int vfio_ap_mdev_get_device_info(unsigned long arg)
> >   	return copy_to_user((void __user *)arg, &info, minsz);
> >   }
> >   
> > +static unsigned long vfio_ap_get_nib(struct kvm *kvm, struct vfio_ap_aqic *parm)
> > +{
> > +	struct s390_io_adapter *adapter;
> > +	struct s390_map_info *map;
> > +	unsigned long nib;
> > +	int found = 0;
> > +
> > +	/* find the adapter */
> > +	if (parm->adapter_id > MAX_S390_IO_ADAPTERS)
> > +		return 0;
> > +
> > +	adapter = kvm->arch.adapters[parm->adapter_id];
> > +	if (!adapter)
> > +		return 0;
> > +
> > +	down_write(&adapter->maps_lock);
> > +	list_for_each_entry(map, &adapter->maps, list) {
> > +		if (map->guest_addr == parm->nib) {
> > +			found = 1;
> > +			break;
> > +		}
> > +	}
> > +	up_write(&adapter->maps_lock);
>
> Regardless of which user space interface you ultimately use: I think
> you should leave poking the adapter handling innards to the adapter
> code and instead create and use an interface to look up the mapping
> from the guest address.

Right...
Thanks

Pierre

> > +
> > +	if (!found)
> > +		return 0;
> > +
> > +	nib = (unsigned long) page_address(map->page);
> > +	nib += (map->guest_addr & 0x0fff);
> > +
> > +	return nib;
> > +}


--
Pierre Morel
Linux/KVM/QEMU in BÃblingen - Germany