On 08/11/2018 10:14, Cornelia Huck wrote:
On Wed, 7 Nov 2018 23:23:40 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
On 07/11/2018 10:46, Cornelia Huck wrote:
On Wed, 31 Oct 2018 19:12:54 +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 | 95 +++++++++++++++++++++++++++++++
1 file changed, 95 insertions(+)
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 272ef427dcc0..f68102163bf4 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -895,12 +895,107 @@ static int vfio_ap_mdev_get_device_info(unsigned long arg)
return copy_to_user((void __user *)arg, &info, minsz);
}
+static int ap_ioctl_setirq(struct ap_matrix_mdev *matrix_mdev,
+ struct vfio_ap_aqic *parm)
+{
+ struct aqic_gisa aqic_gisa = reg2aqic(0);
+ struct kvm_s390_gisa *gisa = matrix_mdev->kvm->arch.gisa;
+ struct ap_status ap_status = reg2status(0);
+ unsigned long p;
+ int ret = -1;
+ int apqn;
+ uint32_t gd;
+
+ apqn = (int)(parm->cmd & 0xffff);
It seems you always use cmd & 0xffff only. What if there is other stuff
in the remaining bits of cmd? Do you plan to ignore it in any case, or
should you actively check that there is nothing in it?
I do not think that the ioctl interface should reflect the hardware
interface.
The ioctl interface ignores the remaining bits.
We ignore the FC because we obviously want to make a AQIC FC=3
We ignore the T bit.
But we receive the information from the intercepting software, i.e. QEMU
which should I think do the checks before using the ioctl interface.
Yes, it should; but you still can't know whether it actually did...
I do not care, I just ignore these bits.
It seemed easier to me to pass the complete registers and to ignore some
bits in them. In case we get any change in the future
But we could also only pass the APQN
I'd prefer to use a well-defined structure that explicitly handles the
userspace<->kernel communication. Not that we start relying on implicit
assumptions and then things break when userspace does something
different...
OK, I can pass a u16 in the ioctl parameters and explicitly reserve the
ignored bits.
Thanks for the review.
Regards,
Pierre
--
Pierre Morel
Linux/KVM/QEMU in Böblingen - Germany
