On Fri, 21 Aug 2020 15:56:07 -0400 Tony Krowiak <[email protected]> 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 <[email protected]> > --- > 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.
