On 15/02/2019 10:49, Cornelia Huck wrote:
On Thu, 14 Feb 2019 14:51:04 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
We need to find the queue with a specific APQN during the
handling of the interception of the PQAP/AQIC instruction.
To handle the AP associated device reference count we keep
track of it in the vfio_ap_queue until we put the device.
So, the relationship is
(struct ap_device)--(driver_data)-->(struct vfio_ap_queue)--(pointer)-->(struct ap_device)
? IOW, a backlink?
If so, can't you already set that up during probe?
Will do.
Or am I confused by the various similar devices again? Maybe a diagram
would help...
No you are right.
Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
---
drivers/s390/crypto/vfio_ap_ops.c | 54 +++++++++++++++++++++++++++++++++++
drivers/s390/crypto/vfio_ap_private.h | 1 +
2 files changed, 55 insertions(+)
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 900b9cf..2a52c9b 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -24,6 +24,60 @@
#define VFIO_AP_MDEV_TYPE_HWVIRT "passthrough"
#define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device"
+/**
+ * vfio_ap_check_apqn: check if a ap_queue is of a given APQN
+ *
+ * Returns 1 if we have a match.
+ * Otherwise returns 0.
+ */
+static int vfio_ap_check_apqn(struct device *dev, void *data)
+{
+ struct vfio_ap_queue *q = dev_get_drvdata(dev);
+
+ return (q->apqn == *(int *)data);
+}
+
+/**
+ * vfio_ap_get_queue: Retrieve a queue with a specific APQN
+ * @apqn: The queue APQN
+ *
+ * Retrieve a queue with a specific APQN from the list of the
+ * devices associated to the vfio_ap_driver.
+ *
+ * The vfio_ap_queue has been already associated with the device
+ * during the probe.
+ * Store the associated device for reference counting
+ *
+ * Returns the pointer to the associated vfio_ap_queue
+ */
+static __attribute__((unused))
Eww. Can you get rid of that by reordering or squashing patches?
I did this to avoid posting a very big patch.
I will of course squash 4 and 5 with patch 6, when the two patches 4 and
5 are reviewed.
If you think it brings more clarity to squash all for the next iteration
I will do.
Regards,
Pierre
--
Pierre Morel
Linux/KVM/QEMU in Böblingen - Germany
