Re: [PATCH v2 3/7] s390: vfio-ap: sysfs interface to display guest CRYCB

From: Tony Krowiak <akrowiak@linux.ibm.com>
To: pmorel@linux.ibm.com, linux-s390@vger.kernel.org,
	linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: freude@linux.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.com,
	frankja@linux.ibm.com, david@redhat.com, schwidefsky@de.ibm.com,
	heiko.carstens@de.ibm.com, pasic@linux.ibm.com,
	alex.williamson@redhat.com, kwankhede@nvidia.com
Subject: Re: [PATCH v2 3/7] s390: vfio-ap: sysfs interface to display guest CRYCB
Date: Mon, 6 May 2019 15:55:08 -0400	[thread overview]
Message-ID: <b0770195-c016-c661-4ca4-dabbffacf332@linux.ibm.com> (raw)
In-Reply-To: <a2361365-050e-dfdd-ccd2-0167ccfcdfbf@linux.ibm.com>

On 5/6/19 2:54 AM, Pierre Morel wrote:
> On 03/05/2019 23:14, Tony Krowiak wrote:
>> 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@linux.ibm.com>
>> ---
>>   drivers/s390/crypto/vfio_ap_ops.c | 59 
>> +++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 59 insertions(+)
>>
>> diff --git a/drivers/s390/crypto/vfio_ap_ops.c 
>> b/drivers/s390/crypto/vfio_ap_ops.c
>> index 44a04b4aa9ae..1021466cb661 100644
>> --- a/drivers/s390/crypto/vfio_ap_ops.c
>> +++ b/drivers/s390/crypto/vfio_ap_ops.c
>> @@ -771,6 +771,64 @@ 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;
>> +    unsigned long naqm_bits;
>> +    int nchars = 0;
>> +    int n;
>> +
>> +    if (!matrix_mdev->shadow_crycb)
>> +        return -ENODEV;
>> +
>> +    mutex_lock(&matrix_dev->lock);
>> +    napm_bits = matrix_mdev->shadow_crycb->apm_max + 1;
>> +    naqm_bits = matrix_mdev->shadow_crycb->aqm_max + 1;
>> +    apid1 = find_first_bit_inv(matrix_mdev->shadow_crycb->apm, 
>> napm_bits);
>> +    apqi1 = find_first_bit_inv(matrix_mdev->shadow_crycb->aqm, 
>> naqm_bits);
>> +
>> +    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,
>> @@ -780,6 +838,7 @@ 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,
>>   };
>>
> 
> Code seems very similar to matrix_show, can't you share the code?

It is, I suppose I could write a function that both can call.

> 
> 
> 
> 
> 