[PATCH v8 11/16] s390/vfio-ap: allow configuration of matrix mdev in use by a KVM guest

From: Tony Krowiak
Date: Fri Jun 05 2020 - 17:41:29 EST


The current support for pass-through crypto adapters does not allow
configuration of a matrix mdev when it is in use by a KVM guest. Let's
allow AP resources - i.e., adapters, domains and control domains - to be
assigned to or unassigned from a matrix mdev while it is in use by a guest.
This is in preparation for the introduction of support for dynamic
configuration of the AP matrix for a running KVM guest.

Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
---
drivers/s390/crypto/vfio_ap_ops.c | 24 ------------------------
1 file changed, 24 deletions(-)

diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 68bdf80807c6..4f59f471b4d3 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -773,10 +773,6 @@ static ssize_t assign_adapter_store(struct device *dev,
struct mdev_device *mdev = mdev_from_dev(dev);
struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);

- /* If the guest is running, disallow assignment of adapter */
- if (matrix_mdev->kvm)
- return -EBUSY;
-
ret = kstrtoul(buf, 0, &apid);
if (ret)
return ret;
@@ -828,10 +824,6 @@ static ssize_t unassign_adapter_store(struct device *dev,
struct mdev_device *mdev = mdev_from_dev(dev);
struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);

- /* If the guest is running, disallow un-assignment of adapter */
- if (matrix_mdev->kvm)
- return -EBUSY;
-
ret = kstrtoul(buf, 0, &apid);
if (ret)
return ret;
@@ -891,10 +883,6 @@ static ssize_t assign_domain_store(struct device *dev,
struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);
unsigned long max_apqi = matrix_mdev->matrix.aqm_max;

- /* If the guest is running, disallow assignment of domain */
- if (matrix_mdev->kvm)
- return -EBUSY;
-
ret = kstrtoul(buf, 0, &apqi);
if (ret)
return ret;
@@ -946,10 +934,6 @@ static ssize_t unassign_domain_store(struct device *dev,
struct mdev_device *mdev = mdev_from_dev(dev);
struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);

- /* If the guest is running, disallow un-assignment of domain */
- if (matrix_mdev->kvm)
- return -EBUSY;
-
ret = kstrtoul(buf, 0, &apqi);
if (ret)
return ret;
@@ -991,10 +975,6 @@ static ssize_t assign_control_domain_store(struct device *dev,
struct mdev_device *mdev = mdev_from_dev(dev);
struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);

- /* If the guest is running, disallow assignment of control domain */
- if (matrix_mdev->kvm)
- return -EBUSY;
-
ret = kstrtoul(buf, 0, &id);
if (ret)
return ret;
@@ -1036,10 +1016,6 @@ static ssize_t unassign_control_domain_store(struct device *dev,
struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);
unsigned long max_domid = matrix_mdev->matrix.adm_max;

- /* If the guest is running, disallow un-assignment of control domain */
- if (matrix_mdev->kvm)
- return -EBUSY;
-
ret = kstrtoul(buf, 0, &domid);
if (ret)
return ret;
--
2.21.1