From: Farhan Ali <alifm@linux.ibm.com>
Subject: s390: vfio-ap: sysfs interface to view matrix mdev matrix
Patch-mainline: v4.20-rc1
Git-commit: 81b2b4b76a733ee479af359db59e1c91e3aad4cd
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: sysfs interface to view matrix mdev matrix

             Provides a sysfs interface to view the AP matrix configured for the
             mediated matrix device.

             The relevant sysfs structures are:

             /sys/devices/vfio_ap/matrix/
             ...... [mdev_supported_types]
             ......... [vfio_ap-passthrough]
             ............ [devices]
             ...............[$uuid]
             .................. matrix

             To view the matrix configured for the mediated matrix device,
             print the matrix file:

             	cat matrix

             Below are examples of the output from the above command:

             Example 1: Adapters and domains assigned
             	Assignments:
             		Adapters 5 and 6
             		Domains 4 and 71 (0x47)

             	Output
             		05.0004
             		05.0047
             		06.0004
             	06.0047

             Examples 2: Only adapters assigned
             	Assignments:
             		Adapters 5 and 6

             	Output:
             		05.
             		06.

             Examples 3: Only domains assigned
             	Assignments:
             		Domains 4 and 71 (0x47)

             	Output:
             		.0004
             		.0047

             Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
             Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
             Reviewed-by: Cornelia Huck <cohuck@redhat.com>
             Tested-by: Michael Mueller <mimu@linux.ibm.com>
             Tested-by: Farhan Ali <alifm@linux.ibm.com>
             Tested-by: Pierre Morel <pmorel@linux.ibm.com>
             Message-Id: <20180925231641.4954-10-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 |   51 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -625,6 +625,56 @@ static ssize_t control_domains_show(stru
 }
 DEVICE_ATTR_RO(control_domains);
 
+static ssize_t 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->matrix.apm_max + 1;
+	unsigned long naqm_bits = matrix_mdev->matrix.aqm_max + 1;
+	int nchars = 0;
+	int n;
+
+	apid1 = find_first_bit_inv(matrix_mdev->matrix.apm, napm_bits);
+	apqi1 = find_first_bit_inv(matrix_mdev->matrix.aqm, naqm_bits);
+
+	mutex_lock(&matrix_dev->lock);
+
+	if ((apid1 < napm_bits) && (apqi1 < naqm_bits)) {
+		for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, napm_bits) {
+			for_each_set_bit_inv(apqi, matrix_mdev->matrix.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->matrix.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->matrix.aqm, naqm_bits) {
+			n = sprintf(bufpos, ".%04lx\n", apqi);
+			bufpos += n;
+			nchars += n;
+		}
+	}
+
+	mutex_unlock(&matrix_dev->lock);
+
+	return nchars;
+}
+DEVICE_ATTR_RO(matrix);
+
 static struct attribute *vfio_ap_mdev_attrs[] = {
 	&dev_attr_assign_adapter.attr,
 	&dev_attr_unassign_adapter.attr,
@@ -633,6 +683,7 @@ static struct attribute *vfio_ap_mdev_at
 	&dev_attr_assign_control_domain.attr,
 	&dev_attr_unassign_control_domain.attr,
 	&dev_attr_control_domains.attr,
+	&dev_attr_matrix.attr,
 	NULL,
 };