On 26/02/2019 19:23, Tony Krowiak wrote:
On 2/22/19 10:29 AM, Pierre Morel wrote:
We register the AP PQAP instruction hook during the open
of the mediated device. And unregister it on release.
In the AP PQAP instruction hook, if we receive a demand to
enable IRQs,
- we retrieve the vfio_ap_queue based on the APQN we receive
in REG1,
- we retrieve the page of the guest address, (NIB), from
register REG2
- we the mediated device to use the VFIO pinning infratrsucture
to pin the page of the guest address,
- we retrieve the pointer to KVM to register the guest ISC
and retrieve the host ISC
- finaly we activate GISA
If we receive a demand to disable IRQs,
- we deactivate GISA
- unregister from the GIB
- unping the NIB
Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
---
arch/s390/include/asm/kvm_host.h | 1 +
drivers/s390/crypto/ap_bus.h | 1 +
drivers/s390/crypto/vfio_ap_ops.c | 199
+++++++++++++++++++++++++++++++++-
drivers/s390/crypto/vfio_ap_private.h | 1 +
4 files changed, 199 insertions(+), 3 deletions(-)
diff --git a/arch/s390/include/asm/kvm_host.h
b/arch/s390/include/asm/kvm_host.h
index 49cc8b0..5f3bb8c 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -720,6 +720,7 @@ struct kvm_s390_cpu_model {
struct kvm_s390_crypto {
struct kvm_s390_crypto_cb *crycb;
int (*pqap_hook)(struct kvm_vcpu *vcpu);
+ void *vfio_private;
...snip...
+ *
+ * Return 0 if we could handle the request inside KVM.
+ * otherwise, returns -EOPNOTSUPP to let QEMU handle the fault.
+ */
+static int handle_pqap(struct kvm_vcpu *vcpu)
Change this function name to handle_pqap_aqic
Since we only intercept AQIC, why not.
+{
+}
Add this function:
static int handle_pqap(struct kvm_vcpu *vcpu)
{
int ret;
uint8_t fc;
fc = vcpu->run->s.regs.gprs[0] >> 24;
switch (fc) {
case 0x03:
ret = handle_pqap_aqic(vcpu);
break;
default:
ret = -EOPNOTSUPP;
break;
}
return ret;
}
It is of no use for now, we only intercept AQIC, why introduce this now?
We can introduce a trampoline when we intercept TAPQ. If we do.
+
+ /*
* vfio_ap_mdev_iommu_notifier: IOMMU notifier callback
*
* @nb: The notifier block
@@ -767,9 +950,10 @@ static int vfio_ap_mdev_iommu_notifier(struct
notifier_block *nb,
if (action == VFIO_IOMMU_NOTIFY_DMA_UNMAP) {
struct vfio_iommu_type1_dma_unmap *unmap = data;
- unsigned long g_pfn = unmap->iova >> PAGE_SHIFT;
+ unsigned long pfn = unmap->iova >> PAGE_SHIFT;
- vfio_unpin_pages(mdev_dev(matrix_mdev->mdev), &g_pfn, 1);
+ if (matrix_mdev->mdev)
+ vfio_unpin_pages(mdev_dev(matrix_mdev->mdev), &pfn, 1);
return NOTIFY_OK;
}
@@ -879,6 +1063,11 @@ static int vfio_ap_mdev_open(struct mdev_device
*mdev)
if (ret)
goto err_group;
+ if (!matrix_mdev->kvm) {
+ ret = -ENODEV;
+ goto err_iommu;
+ }
+
matrix_mdev->iommu_notifier.notifier_call =
vfio_ap_mdev_iommu_notifier;
events = VFIO_IOMMU_NOTIFY_DMA_UNMAP;
@@ -887,6 +1076,8 @@ static int vfio_ap_mdev_open(struct mdev_device
*mdev)
if (ret)
goto err_iommu;
+ matrix_mdev->kvm->arch.crypto.pqap_hook = handle_pqap;
+ matrix_mdev->kvm->arch.crypto.vfio_private = matrix_mdev;
I do not see this used anywhere, why do we need it?
In handle_papq to retrieve the associated mediated device
return 0;
err_iommu:
@@ -905,6 +1096,8 @@ static void vfio_ap_mdev_release(struct
mdev_device *mdev)
kvm_arch_crypto_clear_masks(matrix_mdev->kvm);
vfio_ap_mdev_reset_queues(mdev);
+ matrix_mdev->kvm->arch.crypto.pqap_hook = NULL;
+ matrix_mdev->kvm->arch.crypto.vfio_private = NULL;
Ditto
ditto
vfio_unregister_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY,
&matrix_mdev->group_notifier);
vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY,
diff --git a/drivers/s390/crypto/vfio_ap_private.h
b/drivers/s390/crypto/vfio_ap_private.h
index e535735..e2fd2c0 100644
--- a/drivers/s390/crypto/vfio_ap_private.h
+++ b/drivers/s390/crypto/vfio_ap_private.h
@@ -94,6 +94,7 @@ struct vfio_ap_queue {
struct list_head list;
struct ap_matrix_mdev *matrix_mdev;
unsigned long nib;
+ unsigned long g_pfn;
Can't this be calculated from the nib?
It is.
It is initialized during the IRQ enabling with the current pinned NIB.
While the nib is initialised with the NIB to be use.
This allows to unpin the previous pinned NIB in the case the guest reset
the queue, which automatically disable interrupt, because in this case
the guest will not explicitely disable IRQ by using AQIC.
Regards,
Pierre
--
Pierre Morel
Linux/KVM/QEMU in Böblingen - Germany
