[PATCH v7 10/15] s390/vfio-ap: allow configuration of matrix mdev in use by a KVM guest

From: Tony Krowiak <akrowiak@linux.ibm.com>
To: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org,
	kvm@vger.kernel.org
Cc: freude@linux.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.com,
	mjrosato@linux.ibm.com, pmorel@linux.ibm.com,
	pasic@linux.ibm.com, alex.williamson@redhat.com,
	kwankhede@nvidia.com, jjherne@linux.ibm.com,
	fiuczy@linux.ibm.com, Tony Krowiak <akrowiak@linux.ibm.com>
Subject: [PATCH v7 10/15] s390/vfio-ap: allow configuration of matrix mdev in use by a KVM guest
Date: Tue,  7 Apr 2020 15:20:10 -0400	[thread overview]
Message-ID: <20200407192015.19887-11-akrowiak@linux.ibm.com> (raw)
In-Reply-To: <20200407192015.19887-1-akrowiak@linux.ibm.com>

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@linux.ibm.com>
---
 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 b5cfa3a967c0..4b16d45b702b 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -665,10 +665,6 @@ 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;
@@ -720,10 +716,6 @@ 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;
@@ -810,10 +802,6 @@ 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;
@@ -865,10 +853,6 @@ 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;
@@ -910,10 +894,6 @@ 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;
@@ -955,10 +935,6 @@ 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

