[PATCH v2 2/8] s390: vfio-ap: sysfs interface to display guest CRYCB

From: Tony Krowiak
Date: Sat Apr 20 2019 - 17:50:21 EST


Introduces a sysfs interface on the matrix mdev device to display the
contents of the shadow of the guest's CRYCB

Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
---
drivers/s390/crypto/vfio_ap_ops.c | 58 +++++++++++++++++++++++++++++++++++++++
1 file changed, 58 insertions(+)

diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index b0453e6c20d0..eae4ee24460a 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -750,6 +750,63 @@ static ssize_t matrix_show(struct device *dev, struct device_attribute *attr,
}
static DEVICE_ATTR_RO(matrix);

+static ssize_t guest_matrix_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mdev_device *mdev = mdev_from_dev(dev);
+ struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);
+ char *bufpos = buf;
+ unsigned long apid;
+ unsigned long apqi;
+ unsigned long apid1;
+ unsigned long apqi1;
+ unsigned long napm_bits = matrix_mdev->shadow_crycb->apm_max + 1;
+ unsigned long naqm_bits = matrix_mdev->shadow_crycb->aqm_max + 1;
+ int nchars = 0;
+ int n;
+
+ if (!matrix_mdev->shadow_crycb)
+ return -ENODEV;
+
+ apid1 = find_first_bit_inv(matrix_mdev->shadow_crycb->apm, napm_bits);
+ apqi1 = find_first_bit_inv(matrix_mdev->shadow_crycb->aqm, naqm_bits);
+
+ mutex_lock(&matrix_dev->lock);
+
+ if ((apid1 < napm_bits) && (apqi1 < naqm_bits)) {
+ for_each_set_bit_inv(apid, matrix_mdev->shadow_crycb->apm,
+ napm_bits) {
+ for_each_set_bit_inv(apqi,
+ matrix_mdev->shadow_crycb->aqm,
+ naqm_bits) {
+ n = sprintf(bufpos, "%02lx.%04lx\n", apid,
+ apqi);
+ bufpos += n;
+ nchars += n;
+ }
+ }
+ } else if (apid1 < napm_bits) {
+ for_each_set_bit_inv(apid, matrix_mdev->shadow_crycb->apm,
+ napm_bits) {
+ n = sprintf(bufpos, "%02lx.\n", apid);
+ bufpos += n;
+ nchars += n;
+ }
+ } else if (apqi1 < naqm_bits) {
+ for_each_set_bit_inv(apqi, matrix_mdev->shadow_crycb->aqm,
+ naqm_bits) {
+ n = sprintf(bufpos, ".%04lx\n", apqi);
+ bufpos += n;
+ nchars += n;
+ }
+ }
+
+ mutex_unlock(&matrix_dev->lock);
+
+ return nchars;
+}
+static DEVICE_ATTR_RO(guest_matrix);
+
static struct attribute *vfio_ap_mdev_attrs[] = {
&dev_attr_assign_adapter.attr,
&dev_attr_unassign_adapter.attr,
@@ -759,6 +816,7 @@ static struct attribute *vfio_ap_mdev_attrs[] = {
&dev_attr_unassign_control_domain.attr,
&dev_attr_control_domains.attr,
&dev_attr_matrix.attr,
+ &dev_attr_guest_matrix.attr,
NULL,
};

--
2.7.4