On 9/26/20 3:16 AM, Halil Pasic wrote:
On Fri, 18 Sep 2020 13:09:25 -0400
Tony Krowiak <akrowiak@xxxxxxxxxxxxx> wrote:
On 9/17/20 10:34 AM, Cornelia Huck wrote:
On Fri, 21 Aug 2020 15:56:07 -0400
Tony Krowiak <akrowiak@xxxxxxxxxxxxx> wrote:
The matrix of adapters and domains configured in a guest's CRYCB may
differ from the matrix of adapters and domains assigned to the matrix mdev,
so this patch introduces a sysfs attribute to display the matrix of a guest
using the matrix mdev. For a matrix mdev denoted by $uuid, the crycb for a
guest using the matrix mdev can be displayed as follows:
cat /sys/devices/vfio_ap/matrix/$uuid/guest_matrix
If a guest is not using the matrix mdev at the time the crycb is displayed,
an error (ENODEV) will be returned.
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 efb229033f9e..30bf23734af6 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -1119,6 +1119,63 @@ 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_apcb.apm_max + 1;
+ unsigned long naqm_bits = matrix_mdev->shadow_apcb.aqm_max + 1;
+ int nchars = 0;
+ int n;
+
+ if (!vfio_ap_mdev_has_crycb(matrix_mdev))
+ return -ENODEV;
+
+ apid1 = find_first_bit_inv(matrix_mdev->shadow_apcb.apm, napm_bits);
+ apqi1 = find_first_bit_inv(matrix_mdev->shadow_apcb.aqm, naqm_bits);
+
+ mutex_lock(&matrix_dev->lock);
+
+ if ((apid1 < napm_bits) && (apqi1 < naqm_bits)) {
+ for_each_set_bit_inv(apid, matrix_mdev->shadow_apcb.apm,
+ napm_bits) {
+ for_each_set_bit_inv(apqi,
+ matrix_mdev->shadow_apcb.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_apcb.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_apcb.aqm,
+ naqm_bits) {
+ n = sprintf(bufpos, ".%04lx\n", apqi);
+ bufpos += n;
+ nchars += n;
+ }
+ }
+
+ mutex_unlock(&matrix_dev->lock);
+
+ return nchars;
+}
This basically looks like a version of matrix_show() operating on the
shadow apcb. I'm wondering if we could consolidate these two functions
by passing in the structure to operate on as a parameter? Might not be
worth the effort, though.
We still need the two functions because they back the mdev's
sysfs matrix and guest_matrix attributes, but we could call a function.
I'm not sure it buys us much though.
The logic seems identical with the exception that the guest variant
checks if vfio_ap_mdev_has_crycb(matrix_mdev). I'm not a big fan of
duplicated code, and especially not in such close proximity. I'm voting
for factoring out the common logic.
Not a problem, will do.
Otherwise looks OK.
Regards,
Halil
