From: Tony Krowiak <akrowiak@linux.ibm.com>
To: Halil Pasic <pasic@linux.ibm.com>, Pierre Morel <pmorel@linux.ibm.com>
Cc: borntraeger@de.ibm.com, alex.williamson@redhat.com,
cohuck@redhat.com, linux-kernel@vger.kernel.org,
linux-s390@vger.kernel.org, kvm@vger.kernel.org,
frankja@linux.ibm.com, david@redhat.com, schwidefsky@de.ibm.com,
heiko.carstens@de.ibm.com, freude@linux.ibm.com,
mimu@linux.ibm.com
Subject: Re: [PATCH v4 3/7] s390: ap: associate a ap_vfio_queue and a matrix mdev
Date: Tue, 5 Mar 2019 17:17:36 -0500 [thread overview]
Message-ID: <24030714-fb55-9cd0-7d75-b5e9f6658e3e@linux.ibm.com> (raw)
In-Reply-To: <20190304030935.525f4223@oc2783563651>
On 3/3/19 9:09 PM, Halil Pasic wrote:
> On Fri, 22 Feb 2019 16:29:56 +0100
> Pierre Morel <pmorel@linux.ibm.com> wrote:
>
>> We need to associate the ap_vfio_queue, which will hold the
>> per queue information for interrupt with a matrix mediated device
>> which hold the configuration and the way to the CRYCB.
> [..]
>> +static int vfio_ap_get_all_domains(struct ap_matrix_mdev *matrix_mdev, int apid)
>> +{
>> + int apqi, apqn;
>> + int ret = 0;
>> + struct vfio_ap_queue *q;
>> + struct list_head q_list;
>> +
>> + INIT_LIST_HEAD(&q_list);
>> +
>> + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) {
>> + apqn = AP_MKQID(apid, apqi);
>> + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list);
>> + if (!q) {
>> + ret = -EADDRNOTAVAIL;
>> + goto rewind;
>> + }
>> + if (q->matrix_mdev) {
>> + ret = -EADDRINUSE;
>
> You tried to get the q from matrix_dev->free_list thus modulo races
> q->matrix_mdev should be 0. This change breaks the error codes in a
> sense that it becomes impossible to provoke EADDRINUSE (the proper
> error code for taken by another matrix_mdev).
I don't understand what you are saying here. AFIU, the idea here is to
pull the q from the free list. If there is no q for the apqn on the free
list, then that would indicate the queue has not been bound to a driver
in which case the appropriate rc is EADDRNOTAVAIL. If the queue has
been bound, then a check is done to see whether the queue has been
associated with an mdev device. If so, the rc is -EADDRINUSE, which is
also appropriate. What am I missing?
>
>> + goto rewind;
>> + }
>> + list_move(&q->list, &q_list);
>> + }
>> + move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev);
>> return 0;
>> +rewind:
>> + move_and_set(&q_list, &matrix_dev->free_list, NULL);
>> + return ret;
>> }
>> -
>> /**
>> - * vfio_ap_mdev_verify_no_sharing
>> + * vfio_ap_get_all_cards:
>> *
>> - * Verifies that the APQNs derived from the cross product of the AP adapter IDs
>> - * and AP queue indexes comprising the AP matrix are not configured for another
>> - * mediated device. AP queue sharing is not allowed.
>> + * @matrix_mdev: the matrix mediated device for which we want to associate
>> + * all available queues with a given apqi.
>> + * @apqi: The apqi which associated with all defined APID of the
>> + * mediated device will define a AP queue.
>> *
>> - * @matrix_mdev: the mediated matrix device
>> + * We define a local list to put all queues we find on the matrix device
>> + * free list when associating the apqi with all already defined apid for
>> + * this matrix mediated device.
>> *
>> - * Returns 0 if the APQNs are not shared, otherwise; returns -EADDRINUSE.
>> + * If we can get all the devices we roll them to the mediated device list
>> + * If we get errors we unroll them to the free list.
>> */
>> -static int vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev *matrix_mdev)
>> +static int vfio_ap_get_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi)
>> {
>> - struct ap_matrix_mdev *lstdev;
>> - DECLARE_BITMAP(apm, AP_DEVICES);
>> - DECLARE_BITMAP(aqm, AP_DOMAINS);
>> -
>> - list_for_each_entry(lstdev, &matrix_dev->mdev_list, node) {
>> - if (matrix_mdev == lstdev)
>> - continue;
>> -
>> - memset(apm, 0, sizeof(apm));
>> - memset(aqm, 0, sizeof(aqm));
>> -
>> - /*
>> - * We work on full longs, as we can only exclude the leftover
>> - * bits in non-inverse order. The leftover is all zeros.
>> - */
>> - if (!bitmap_and(apm, matrix_mdev->matrix.apm,
>> - lstdev->matrix.apm, AP_DEVICES))
>> - continue;
>> -
>> - if (!bitmap_and(aqm, matrix_mdev->matrix.aqm,
>> - lstdev->matrix.aqm, AP_DOMAINS))
>> - continue;
>> -
>> - return -EADDRINUSE;
>> + int apid, apqn;
>> + int ret = 0;
>> + struct vfio_ap_queue *q;
>> + struct list_head q_list;
>> + struct ap_matrix_mdev *tmp = NULL;
>> +
>> + INIT_LIST_HEAD(&q_list);
>> +
>> + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) {
>> + apqn = AP_MKQID(apid, apqi);
>> + q = vfio_ap_get_queue(apqn, &matrix_dev->free_list);
>> + if (!q) {
>> + ret = -EADDRNOTAVAIL;
>> + goto rewind;
>> + }
>> + if (q->matrix_mdev) {
>> + ret = -EADDRINUSE;
>
> Same here!
>
> Regards,
> Halil
>
>> + goto rewind;
>> + }
>> + list_move(&q->list, &q_list);
>> }
>
> [..]
>
next prev parent reply other threads:[~2019-03-05 22:17 UTC|newest]
Thread overview: 79+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-22 15:29 [PATCH v4 0/7] vfio: ap: AP Queue Interrupt Control Pierre Morel
2019-02-22 15:29 ` [PATCH v4 1/7] s390: ap: kvm: add PQAP interception for AQIC Pierre Morel
2019-02-25 18:36 ` Tony Krowiak
2019-02-26 11:47 ` Pierre Morel
2019-02-26 15:47 ` Tony Krowiak
2019-02-27 8:09 ` Pierre Morel
2019-02-27 9:13 ` Cornelia Huck
2019-02-27 10:16 ` Pierre Morel
2019-02-27 18:00 ` Tony Krowiak
2019-02-28 9:42 ` Christian Borntraeger
2019-02-28 11:03 ` Christian Borntraeger
2019-02-28 11:22 ` Cornelia Huck
2019-02-28 13:16 ` Pierre Morel
2019-02-28 13:52 ` Cornelia Huck
2019-02-28 14:14 ` Pierre Morel
2019-03-01 12:03 ` Pierre Morel
2019-03-01 12:05 ` Christian Borntraeger
2019-03-01 12:36 ` Cornelia Huck
2019-03-01 15:32 ` Pierre Morel
2019-02-28 13:10 ` Pierre Morel
2019-02-28 15:36 ` Tony Krowiak
2019-02-28 12:39 ` Halil Pasic
2019-02-28 14:12 ` Pierre Morel
2019-02-28 16:51 ` Halil Pasic
2019-03-01 12:10 ` Pierre Morel
2019-02-28 15:43 ` Tony Krowiak
2019-02-28 13:23 ` Pierre Morel
2019-02-28 13:44 ` Christian Borntraeger
2019-02-28 13:47 ` Pierre Morel
2019-02-28 14:07 ` Halil Pasic
2019-02-28 14:13 ` Pierre Morel
2019-02-28 15:45 ` Tony Krowiak
2019-02-28 15:35 ` Tony Krowiak
2019-03-01 8:42 ` Christian Borntraeger
2019-02-28 8:31 ` Christian Borntraeger
2019-02-22 15:29 ` [PATCH v4 2/7] s390: ap: new vfio_ap_queue structure Pierre Morel
2019-02-26 16:10 ` Tony Krowiak
2019-02-27 8:40 ` Pierre Morel
2019-02-27 20:35 ` Tony Krowiak
2019-02-22 15:29 ` [PATCH v4 3/7] s390: ap: associate a ap_vfio_queue and a matrix mdev Pierre Morel
2019-02-26 18:14 ` Tony Krowiak
2019-02-27 9:29 ` Pierre Morel
2019-02-27 20:14 ` Tony Krowiak
2019-02-27 9:32 ` Cornelia Huck
2019-02-27 10:21 ` Pierre Morel
2019-02-27 10:44 ` Pierre Morel
2019-02-27 20:53 ` Tony Krowiak
2019-03-04 2:09 ` Halil Pasic
2019-03-04 10:19 ` Pierre Morel
2019-03-05 22:17 ` Tony Krowiak [this message]
2019-03-12 21:39 ` Tony Krowiak
2019-03-13 10:19 ` Pierre Morel
2019-02-22 15:29 ` [PATCH v4 4/7] vfio: ap: register IOMMU VFIO notifier Pierre Morel
2019-02-27 9:42 ` Cornelia Huck
2019-02-27 10:22 ` Pierre Morel
2019-02-28 8:23 ` Christian Borntraeger
2019-02-28 8:48 ` Pierre Morel
2019-02-28 16:55 ` Halil Pasic
2019-03-01 7:51 ` Christian Borntraeger
2019-02-22 15:29 ` [PATCH v4 5/7] s390: ap: implement PAPQ AQIC interception in kernel Pierre Morel
2019-02-26 18:23 ` Tony Krowiak
2019-02-27 9:54 ` Pierre Morel
2019-02-27 18:17 ` Tony Krowiak
2019-02-27 18:18 ` Tony Krowiak
2019-02-28 20:20 ` Christian Borntraeger
2019-03-01 9:35 ` Pierre Morel
2019-03-04 1:57 ` Halil Pasic
2019-03-04 9:47 ` Pierre Morel
2019-02-22 15:29 ` [PATCH v4 6/7] s390: ap: Cleanup on removing the AP device Pierre Morel
2019-02-26 18:27 ` Tony Krowiak
2019-02-27 9:58 ` Pierre Morel
2019-03-04 13:02 ` Cornelia Huck
2019-03-08 22:43 ` Tony Krowiak
2019-03-11 8:31 ` Pierre Morel
2019-03-12 21:53 ` Tony Krowiak
2019-03-13 10:15 ` Pierre Morel
2019-02-22 15:30 ` [PATCH v4 7/7] s390: ap: kvm: Enable PQAP/AQIC facility for the guest Pierre Morel
2019-02-28 15:08 ` [PATCH v4 0/7] vfio: ap: AP Queue Interrupt Control Halil Pasic
2019-03-01 9:40 ` Pierre Morel
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=24030714-fb55-9cd0-7d75-b5e9f6658e3e@linux.ibm.com \
--to=akrowiak@linux.ibm.com \
--cc=alex.williamson@redhat.com \
--cc=borntraeger@de.ibm.com \
--cc=cohuck@redhat.com \
--cc=david@redhat.com \
--cc=frankja@linux.ibm.com \
--cc=freude@linux.ibm.com \
--cc=heiko.carstens@de.ibm.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-s390@vger.kernel.org \
--cc=mimu@linux.ibm.com \
--cc=pasic@linux.ibm.com \
--cc=pmorel@linux.ibm.com \
--cc=schwidefsky@de.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).