From: Farhan Ali <alifm@linux.ibm.com>
Subject: s390: vfio-ap: zeroize the AP queues
Patch-mainline: v4.20-rc1
Git-commit: 46a7263d4746a2659edafcb885e91e58bb6d3a2e
References: FATE#326370, LTC#169186, bsc#1113483
Summary: kernel: AP Crypto Passthrough
Description: This adds support for AP crypto passthrough for
kvm guests.
Upstream-Description:
s390: vfio-ap: zeroize the AP queues
Let's call PAPQ(ZAPQ) to zeroize a queue for each queue configured
for a mediated matrix device when it is released.
Zeroizing a queue resets the queue, clears all pending
messages for the queue entries and disables adapter interruptions
associated with the queue.
Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Farhan Ali <alifm@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20180925231641.4954-14-akrowiak@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
drivers/s390/crypto/vfio_ap_ops.c | 49 ++++++++++++++++++++++++++++++++++++++
1 file changed, 49 insertions(+)
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -819,6 +819,54 @@ static int vfio_ap_mdev_group_notifier(s
return NOTIFY_OK;
}
+static int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi,
+ unsigned int retry)
+{
+ struct ap_queue_status status;
+
+ do {
+ status = ap_zapq(AP_MKQID(apid, apqi));
+ switch (status.response_code) {
+ case AP_RESPONSE_NORMAL:
+ return 0;
+ case AP_RESPONSE_RESET_IN_PROGRESS:
+ case AP_RESPONSE_BUSY:
+ msleep(20);
+ break;
+ default:
+ /* things are really broken, give up */
+ return -EIO;
+ }
+ } while (retry--);
+
+ return -EBUSY;
+}
+
+static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev)
+{
+ int ret;
+ int rc = 0;
+ unsigned long apid, apqi;
+ struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);
+
+ for_each_set_bit_inv(apid, matrix_mdev->matrix.apm,
+ matrix_mdev->matrix.apm_max + 1) {
+ for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm,
+ matrix_mdev->matrix.aqm_max + 1) {
+ ret = vfio_ap_mdev_reset_queue(apid, apqi, 1);
+ /*
+ * Regardless whether a queue turns out to be busy, or
+ * is not operational, we need to continue resetting
+ * the remaining queues.
+ */
+ if (ret)
+ rc = ret;
+ }
+ }
+
+ return rc;
+}
+
static int vfio_ap_mdev_open(struct mdev_device *mdev)
{
struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);
@@ -849,6 +897,7 @@ static void vfio_ap_mdev_release(struct
if (matrix_mdev->kvm)
kvm_arch_crypto_clear_masks(matrix_mdev->kvm);
+ vfio_ap_mdev_reset_queues(mdev);
vfio_unregister_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY,
&matrix_mdev->group_notifier);
matrix_mdev->kvm = NULL;